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.In physics, thermodynamics (from the Greek θέρμη therme, meaning "heat"[1] and δύναμις, dynamis, meaning "power") is the study of energy conversion between heat and mechanical work, and subsequently the macroscopic variables such as temperature, volume and pressure.^ Thermodynamics, plasma physics, and quantum mechanics .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ Mechanical work can be turned into heat.
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^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
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.Its progenitor, based on statistical predictions of the collective motion of particles from their microscopic behavior, is the field of statistical thermodynamics (or statistical mechanics), a branch of statistical physics.^ Even the foundations of statistical mechanics were unsettled as thermodynamicists questioned how the second law of thermodynamics could be reconciled with reversible microscopic equations of motion.
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^ This analysis suggests that the function and structure of ecosystems follows the development path predicted by the behavior of nonequilibrium thermodynamic structures.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ The father of statistical thermodynamics, Boltzmann recognized the apparent contradiction between the thermodynamically predicted randomized cold death of the universe and the existence of a process (i.e.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

[2][3][4] .Historically, thermodynamics developed out of need to increase the efficiency of early steam engines.^ Thus, we derive from the first law of thermodynamics that the change in the energy of a system ( E) is equal to the work done on (or by) the system ( W) and the heat flow into (or out of) the system ( Q) Mechanical work and energy are interchangeable, i.e., energy may be converted into mechanical work as in a steam engine, or mechanical work can be converted into energy as in the heating of a cannon which occurs as its barrel is bored.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Something that was roughly the 2nd law was stated by French engineer Sadi Carnot in 1824 with regard to the efficiency of steam engines.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Thermodynamics, largely driven into being by the steam engine, should be pushed into a further mature stage, driven by the nanotechnology that controls matter on the atomic scale.
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[5]
.
Typical thermodynamic system, showing input from a heat source (boiler) on the left and output to a heat sink (condenser) on the right.
^ An attribute function Arity : 2 Attribute-Function-Of : 2-input-control-volume Defined in theory: Thermodynamics No source file available.
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^ An attribute function Arity : 2 Attribute-Function-Of : 1-input-thermal-component Defined in theory: Thermodynamics No source file available.
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^ If this structure is removed, allowing the heat source to come into contact with the heat sink, the system decays back to equilibrium.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

Work is extracted, in this case by a series of pistons.

Contents

Introduction

Thermodynamic equations
Laws of thermodynamics
Conjugate variables
Thermodynamic potential
Material properties
Maxwell relations
Bridgman's equations
Table of thermodynamic equations
edit
.The starting point for most thermodynamic considerations are the laws of thermodynamics, which postulate that energy can be exchanged between physical systems as heat or work.^ I work in energy systems.
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^ We assume the systems are only able to exchange heat energy with each other, d E 1 =-d E 2 , so .

^ It is a law of heat and energy distribution within a closed system.
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[6] .They also postulate the existence of a quantity named entropy, which can be defined for any isolated system that is in thermodynamic equilibrium.^ You can apply thermodynamics to an "isolated system".
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^ No need to define T for isolated systems .
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^ Thare have been similar dissussions on wether thermodynamics (equilibrium theory) can be applied to small systems of finite size (such as nanostructures), because they are in principle "metastable" (relative to bulk).
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[7] In thermodynamics, interactions between large ensembles of objects are studied and categorized. Central to this are the concepts of system and surroundings. .A system is composed of particles, whose average motions define its properties, which in turn are related to one another through equations of state.^ Thus, the small system fluctuates from one quantum state to another quantum state.
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^ It is difficult to imagine how one could ever couple random thermal energy flow through the system to do the required configurational entropy work of selecting and sequencing.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Note, by the premises of kinetic theory, it really does not matter whether the system description carries one particle or N particles.
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.Properties can be combined to express internal energy and thermodynamic potentials, which are useful for determining conditions for equilibrium and spontaneous processes.^ We can readily see the difficulty in getting polymerization reactions to occur under equilibrium conditions, i.e., in the absence of such an energy flow.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Thermodynamics When you use energy, the rules are very well defined.
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^ We therefore conclude that, given the availability of energy and an appropriate coupling mechanism, the maintenance of a living system far from equilibrium presents no thermodynamic problems.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.With these tools, the usage of thermodynamics describes how systems respond to changes in their surroundings.^ We take the restated laws of thermodynamics of Hatsopoulos and Keenan and Kestin and extend them so that in nonequilibrium regions processes and systems can be described in terms of gradients maintaining systems away from equilibrium.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ The thermodynamic imperative of the restated second law is that these systems will strive to reduce this gradient by all physical and chemical processes available to them.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ By examining the entropy changes and entropy production of such systems Ishida has formulated a nonequilibrium thermodynamics of the hypercycles.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

.This can be applied to a wide variety of topics in science and engineering, such as engines, phase transitions, chemical reactions, transport phenomena, and even black holes.^ Libelle on December 30, 2008 - 6:45pm I doubt that one in a thousand people who post here can even apply them to steam engines.
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^ Mechanica is powered by Drupal , and hosted at the Harvard School of Engineering and Applied Sciences .
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^ Of course any textbook on thermodynamics (a topic taught in Physics, Chemistry, and Chemical and Mechanical Engineering) will cover these topics.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

.The results of thermodynamics are essential for other fields of physics and for chemistry, chemical engineering, aerospace engineering, mechanical engineering, cell biology, biomedical engineering, materials science, and economics to name a few.^ Of course any textbook on thermodynamics (a topic taught in Physics, Chemistry, and Chemical and Mechanical Engineering) will cover these topics.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Now it’s not too difficult to see how the configurational and thermodynamic dispersals (and their associated notions of entropy) are simple physical implementations of the above mathematical result.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

^ Ultimately, chemistry, biology, the Earth sciences, et cetera, must be bale to be explained completely by physics (although it is currently highly impractical).
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

[8][9]

Developments

Sadi Carnot (1796-1832), the father of thermodynamics
.The history of thermodynamics as a scientific discipline generally begins with Otto von Guericke who, in 1650, built and designed the world's first vacuum pump and demonstrated a vacuum using his Magdeburg hemispheres.^ The history of research in the area of thermodynamics has proven how easily it is to be certain we know things, only to find out later that we were beginning from completely false premises.
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^ I might add, though, that I have made a pair of presentations on thermodynamics and its application to power generation to a group of economists who work in my organisation.
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Guericke was driven to make a vacuum in order to disprove Aristotle's long-held supposition that 'nature abhors a vacuum'. Shortly after Guericke, the Irish physicist and chemist Robert Boyle had learned of Guericke's designs and, in 1656, in coordination with English scientist Robert Hooke, built an air pump.[10] .Using this pump, Boyle and Hooke noticed a correlation between pressure, temperature, and volume.^ The volume of 1 kg of neon gas as a function of temperature (at standard pressure).

^ Liquid gallium is used in the nanothermometer because the gallium volume changes linearly with temperature - rising up and down the tube - at a consistent rate when the tube was exposed to different temperatures.
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^ Find the volume of one mole of an ideal gas, in units of liters, at standard temperature and pressure (0°C and 101 kPa).

.In time, Boyle's Law was formulated, which states that pressure and volume are inversely proportional.^ If we combine the first and second laws as expressed in equations 7-1 and 7-2 and replace the mechanical work term W by P V, where P is pressure and V is volume change, we obtain, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Pressure is proportional to temperature when volume is held constant.

^ The only thermodynamic statement available was the second law itself, stating that, for large systems and over long times, the entropy production rate is necessarily positive.
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.Then, in 1679, based on these concepts, an associate of Boyle's named Denis Papin built a bone digester, which was a closed vessel with a tightly fitting lid that confined steam until a high pressure was generated.^ Heat always flows spontaneously from a hotter reservoir to a colder reservoir until there is no longer a temperature difference or gradient; gas will always flow from high pressure to low pressure until there is no longer a pressure difference or gradient.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

Later designs implemented a steam release valve that kept the machine from exploding. By watching the valve rhythmically move up and down, Papin conceived of the idea of a piston and a cylinder engine. He did not, however, follow through with his design. .Nevertheless, in 1697, based on Papin's designs, engineer Thomas Savery built the first engine.^ Nature is built to account for failure through trial and error, engineering is built to avoid failure through predictable design.
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Although these early engines were crude and inefficient, they attracted the attention of the leading scientists of the time. .Their work led 127 years later to Sadi Carnot, the "father of thermodynamics", who, in 1824, published Reflections on the Motive Power of Fire, a discourse on heat, power, and engine efficiency.^ Thus a Carnot engine is the most efficient possible heat engine.

^ Example 21: Efficiency of the Carnot engine .

^ For our proof of the efficiency of the Carnot engine, we need only the ratio of Q H to Q L , so we neglect constants of proportionality, and simply subsitutde P ∝ T / V , giving The efficiency of a heat engine is .

The paper outlined the basic energetic relations between the Carnot engine, the Carnot cycle, and Motive power. .It marked the start of thermodynamics as a modern science.^ Because the basic tenets of this paper are built on the principles of modern thermodynamics, we start this paper with a brief discussion of thermodynamics.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

[3]. .The term thermodynamics was coined by James Joule in 1849 to designate the science of relations between heat and power.^ I don't like to think of entropy or the second law of thermodynamics as relating to anything other than irreversibilities in work/heat producing processes.
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^ The first law arose from efforts to understand the relation between heat and work.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ So some creationists, recognizing that their argument fails for the thermodynamic entropy, assert it in terms of the information entropy, which talks about things related to complexity and disorder.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

[3] .By 1858, "thermo-dynamics", as a functional term, was used in William Thomson's paper An Account of Carnot's Theory of the Motive Power of Heat.[11] The first thermodynamic textbook was written in 1859 by William Rankine, originally trained as a physicist and a civil and mechanical engineering professor at the University of Glasgow.^ Mechanical engineering thermodynamics .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ Heat engineering , Sound , Thermodynamics .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ Heat and thermodynamics: an intermediate textbook .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

[12]
.Classical thermodynamics is the early 1800s variation of the original thermodynamics, concerned with thermodynamic states and properties, such as energy, work and heat, and with the laws of thermodynamics, all lacking an atomic interpretation.^ This thermodynamic law does not state that heat cannot become concentrated.
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^ What's the state of Thermodynamic laws in nano-scale?
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^ Be these mechanical or chemical, the first law of thermodynamics---the principle of the Conservation of Energy---tells us that the total energy of the universe or any isolated part of it will be the same after any such transformation as it was before.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

In precursory form, classical thermodynamics derives from chemist Robert Boyle’s 1662 postulate that the pressure P of a given quantity of gas varies inversely as its volume V at constant temperature; i.e. in equation form: PV = k, a constant. .From here, a semblance of a thermo-science began to develop with the construction of the first successful atmospheric steam engines in England by Thomas Savery in 1697 and Thomas Newcomen in 1712. The first and second laws of thermodynamics emerged simultaneously in the 1850s, primarily out of the works of William Rankine, Rudolf Clausius, and William Thomson (Lord Kelvin).^ This is what William Thomson (later Lord Kelvin) did in 1848.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The second law of thermodynamics requires, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Here is a summary of the laws of thermodynamics: .

.With the development of atomic and molecular theories in the late 1800s and early 1900s, thermodynamics was given a molecular interpretation.^ Historically, however, the laws of thermodynamics were discovered in the eighteenth century, when the atomic theory of matter was generally considered to be a hypothesis that couldn't be tested experimentally.

^ Instance-Of : Constant-quantity Quantity.Dimension : Molecular-weight-dimension Axioms: ( = Kg/Mol ( / Kilogram Mole )) Defined in theory: Thermodynamics Source code: thermodynamics.lisp .
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^ Instance-Of : Physical-dimension Axioms: ( = Molecular-Weight-Dimension ( / Mass-Dimension Amount-Dimension )) Defined in theory: Thermodynamics Source code: thermodynamics.lisp .
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

.This field, called statistical mechanics or statistical thermodynamics, relates the microscopic properties of individual atoms and molecules to the macroscopic or bulk properties of materials that can be observed in everyday life, thereby explaining thermodynamics as a natural result of statistics and mechanics (classical and quantum) at the microscopic level.^ Statistical mechanics and the foundations of thermodynamics .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ Introduction to thermodynamics : classical and statistical .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ Thermodynamics, plasma physics, and quantum mechanics .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

.The statistical approach is in contrast to classical thermodynamics, which is a more phenomenological approach that does not include microscopic details.^ This approach is called macroscopic in contrast to the microscopic method of attack.

^ I have a Ph.D. in Chemical Engineering (UC-Berkeley, 1988), specializing in Molecular Thermodynamics, which combines classical and statistical thermodynamics to describe the thermophysical properties of fluids.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Now that we have a microscopic understanding of entropy, what does that tell us about the second law of thermodynamics?

.The foundations of statistical thermodynamics were set out by physicists such as James Clerk Maxwell, Ludwig Boltzmann, Max Planck, Rudolf Clausius and J. Willard Gibbs.^ Statistical mechanics and the foundations of thermodynamics .
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ Treatise on thermodynamics, by Max Planck.
  • Fermilab Library Book Catalog 10 January 2010 17:12 UTC www-spires.fnal.gov [Source type: General]

^ The father of statistical thermodynamics, Boltzmann recognized the apparent contradiction between the thermodynamically predicted randomized cold death of the universe and the existence of a process (i.e.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

.Chemical thermodynamics is the study of the interrelation of energy with chemical reactions or with a physical change of state within the confines of the laws of thermodynamics.^ What's the state of Thermodynamic laws in nano-scale?
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^ You_Are_A_Super_Player 06-08-2007, 11:24 PM The second law of thermodynamics pertains to matter and energy.
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^ In this example, we have attained a state that is now maximally useless in the utilization of the energy that is still there (The First Law of Thermodynamics) but cannot be restored to its original form.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

.During the years 1873-76 the American mathematical physicist Josiah Willard Gibbs published a series of three papers, the most famous being On the Equilibrium of Heterogeneous Substances, in which he showed how thermodynamic processes could be graphically analyzed, by studying the energy, entropy, volume, temperature and pressure of the thermodynamic system in such a manner, one can determine if a process would occur spontaneously.^ The entropy change for a system is defined mathematically as the flow of energy divided by the temperature, or, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ One can follow the thermodynamics of irreversible processes to anaylze how the system as a whole approaches a state of equilibrium.
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^ In equilibrium, the energies of the two systems need not be equal, but the temperatures of the two systems are equal.
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[13] .During the early 20th century, chemists such as Gilbert N. Lewis, Merle Randall, and E. A. Guggenheim began to apply the mathematical methods of Gibbs to the analysis of chemical processes.^ An example is the hypothetical origin of life from normal chemical processes, which has been compared to unlikely occurrences such as the assembly of a 747 by a tornado passing through a junkyard.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ This is because some of the chemical energy is converted by a process into something we want, such as moving a vehicle or making electrons flow.
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[14]

The Four Laws

.The present article is focused on classical thermodynamics, which is focused on systems in thermodynamic equilibrium.^ We take the restated laws of thermodynamics of Hatsopoulos and Keenan and Kestin and extend them so that in nonequilibrium regions processes and systems can be described in terms of gradients maintaining systems away from equilibrium.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ The reason that our restatement of the second law is a significant step forward for thermodynamics is that it tell us how systems will behave as they are moved away from equilibrium.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ Our expansion of the second law immediately applies to complex systems in nonequilibrium settings unlike classical statements which are restricted to equilibrium or near equilibrium conditions.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

.It is wise to distinguish classical thermodynamics from non-equilibrium thermodynamics, which is concerned with systems that are not in thermodynamic equilibrium.^ We take the restated laws of thermodynamics of Hatsopoulos and Keenan and Kestin and extend them so that in nonequilibrium regions processes and systems can be described in terms of gradients maintaining systems away from equilibrium.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ Our expansion of the second law immediately applies to complex systems in nonequilibrium settings unlike classical statements which are restricted to equilibrium or near equilibrium conditions.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ Thermodynamics does not do so well describing systems that are far from equilibrium.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.In thermodynamics, there are four laws that do not depend on the details of the systems under study or how they interact.^ In this context the second law mandates that as systems are moved away from equilibrium they will take advantage of all means available to them to resist externally applied gradients.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ The total closed system is subject to the 2nd law of thermodynamics.
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^ We take the restated laws of thermodynamics of Hatsopoulos and Keenan and Kestin and extend them so that in nonequilibrium regions processes and systems can be described in terms of gradients maintaining systems away from equilibrium.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

.Hence these laws are very generally valid, can be applied to systems about which one knows nothing other than the balance of energy and matter transfer.^ Some forms of energy are more convenient than others in certain situations.

^ "It has been estimated that those chance errors occur at a rate of about one per several hundred million cells in each generation.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ In this context the second law mandates that as systems are moved away from equilibrium they will take advantage of all means available to them to resist externally applied gradients.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

.Examples of such systems include Einstein's prediction, around the turn of the 20th century, of spontaneous emission, and ongoing research into the thermodynamics of black holes.^ Our work examines the thermodynamic development of natural systems and as such explains things in terms of macroscopic behaviour of energy processing.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ Black holes are commonly observed to suck hot gas into them.

^ By examining the entropy changes and entropy production of such systems Ishida has formulated a nonequilibrium thermodynamics of the hypercycles.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

These four laws are:
If two thermodynamic systems are separately in thermal equilibrium with a third, they are also in thermal equilibrium with each other.
If we grant that all systems are (trivially) in thermal equilibrium with themselves, the Zeroth law implies that thermal equilibrium is an equivalence relation on the set of thermodynamic systems. .This law is tacitly assumed in every measurement of temperature.^ The heat engine is the root of the idea of entropy and of the absolute temperature scale, but the implications of both laws cover everything we do and indeed every process.
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.Thus, if we want to know if two bodies are at the same temperature, it is not necessary to bring them into contact and to watch whether their observable properties change with time.^ If we make they contact with a large system, this may destroy the states of the real systems and make them have the same temperature of the large system itself.
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^ But without even having constructed a temperature scale, we can see that the important point is the phenomenon of thermal equilibrium itself: two objects left in contact will approach the same temperature.

^ Thus, in thermal contact, the sum of the energies in the two systems is constant, but the sum of the temperatures of the two systems need not be constant.
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[15]
.This law was considered so obvious it was added as a virtual after thought, hence the designation Zeroth, rather than Fourth.^ Hence this version of the zeroth law: .
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.In short, if the heat energy of material A is equal to the heat energy of material B, and B is equal to the heat energy of material C. then A and C must also be equal.^ Conservation of energy therefore tells us that work done by the gas must be exactly balanced by the amount of heat transferred in from the reservoir.

^ The efficiency of a heat engine equals the amount of useful work extracted, W , divided by the amount of energy we had to pay for in order to heat the hot reservoir.

^ Since we expect the energy to be equally shared among x , y , and z motion, 1 the quantity inside the sum must therefore equal 2/3 of the total kinetic energy, so .

The change in the internal energy of a closed thermodynamic system is equal to the sum of the amount of heat energy supplied to or removed from the system and the work done on or by the system or we can say " In an isolated system the heat is constant".
The total entropy of any isolated thermodynamic system always increases over time, approaching a maximum value or we can say " in an isolated system, the entropy never decreases". Another way to phrase this: Heat cannot spontaneously flow from a colder location to a hotter area - work is required to achieve this.
As a system asymptotically approaches absolute zero of temperature all processes virtually cease and the entropy of the system asymptotically approaches a minimum value; also stated as: ."the entropy of all systems and of all states of a system is zero at absolute zero" or equivalently "it is impossible to reach the absolute zero of temperature by any finite number of processes". Absolute zero, at which all activity would stop if it were possible to happen, is −273.15 °C (degrees Celsius), or −459.67 °F (degrees Fahrenheit) or 0 K (kelvins, formerly sometimes degrees absolute).^ It impossible to reach absolute zero in a finite number of steps.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ He defined the entropy of a system in terms of the number of different states available to it.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ {Microscopic definition of entropy} The entropy of a system is S = k ln M , where M is the number of available states.

.See also: Bose–Einstein condensate and negative temperature.^ It might, for instance, be a strange quantum-mechanical state called the Bose-Einstein condensate, which was achieved for the first time recently with macroscopic amounts of atoms.

Potentials

.As can be derived from the energy balance equation (or Burks' equation) on a thermodynamic system there exist energetic quantities called thermodynamic potentials, being the quantitative measure of the stored energy in the system.^ December 31, 2008 - 3:17am Thermodynamics, and in particular measuring efficiencies in exergy, can illuminate many energy choices confronting us.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Since their arguments do not work in terms of thermodynamics, some anti-evolutionists turn to information theory, which contains a quantity called entropy.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ T = change in the logarithm of the number of quantum states divided by the change in the energy of the system, everything else being fixed.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

The five most well known potentials are:
Internal energy U=T S - p V + \sum_i \mu_i N_i\,
Helmholtz free energy A=U-TS\,
Enthalpy H=U+pV\,
Gibbs free energy G=U+pV-TS\,
Grand potential \Phi_{G}=U-TS-\mu N\,
Other thermodynamic potentials can be obtained through Legendre transformation. .Potentials are used to measure energy changes in systems as they evolve from an initial state to a final state.^ The entropy change for a system is defined mathematically as the flow of energy divided by the temperature, or, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ They are able to demonstrate mathematically that within a system that was initially homogeneous, one may subsequently have a periodic, spatial variation of concentration.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ T = change in the logarithm of the number of quantum states divided by the change in the energy of the system, everything else being fixed.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.The potential used depends on the constraints of the system, such as constant temperature or pressure.^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Show that under conditions of standard pressure and temperature, the volume of a sample of an ideal gas depends only on the number of molecules in it.

^ Pressure is proportional to temperature when volume is held constant.

.Internal energy is the internal energy of the system, enthalpy is the internal energy of the system plus the energy related to pressure-volume work, and Helmholtz and Gibbs energy are the energies available in a system to do useful work when the temperature and volume or the pressure and temperature are fixed, respectively.^ The entropy change for a system is defined mathematically as the flow of energy divided by the temperature, or, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Morowitz 15 has estimated more generally that the chemical work, or average increase in enthalpy, for macromolecule formation in living systems is 16.4 cal/gm.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ It includes the equivalence of heat and work, but is more general than that, in that there are many forms of energy that are interconvertible, but with the total for an isolated system remaining constant over time.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

System models

System boundary.svg
An important concept in thermodynamics is the “system”. .Everything in the universe except the system is known as surroundings.^ Everything in the universe that is not a part of the system is the surroundings .
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Everything in the universe that is not a part of the system is the surroundings.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ The first law of thermodynamics, also known as the law of conservation of energy, states that the total energy of any system remains the same, except to the extent it exchanges energy with its surroundings.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

A system is the region of the universe under study. .A system is separated from the remainder of the universe by a boundary which may be imaginary or not, but which by convention delimits a finite volume.^ Along the boundary between the closed system and the surroundings, the temperature may be different from the system temperature, allowing energy flow into or out of the system as it moves toward equilibrium.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ As discuss here, one may always calculate temperature by the Boltzman distribution of quantum states or avearging over kinetic energy of atoms (in MD simulation), but the volume of a finite system is in fact somewhat "arbitrary", without a definite position of boundary.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.The possible exchanges of work, heat, or matter between the system and the surroundings take place across this boundary.^ Along the boundary between the closed system and the surroundings, the temperature may be different from the system temperature, allowing energy flow into or out of the system as it moves toward equilibrium.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ No matter what conversions take place in a isolated system, its total energy (and hence mass) remains constant.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ As a matter of fact, one is left with so constraining the system at the boundaries that ordering is inevitable from the structuring of the environment by the chemist.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

Boundaries are of four types: fixed, moveable, real, and imaginary.
.Basically, the “boundary” is simply an imaginary dotted line drawn around a volume of something when there is going to be a change in the internal energy of that something.^ However, for a nanoscale system the energy changes are associated with volume change which cannot be ignored as in macroscopic systems.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ For as I walked around and looked carefully at your objects of worship, I even found an altar with this inscription: TO AN UNKNOWN GOD. Now what you worship as something unknown I am going to proclaim to you.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Enthalpy adds the product of pressure and specific volume, thus capturing the amount of energy transferred when something crosses a control boundary.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.Anything that passes across the boundary that effects a change in the internal energy of the something needs to be accounted for in the energy balance equation.^ How do the heat flows and effects inside the jar relate to the equation dS > = dq/T? Just to head you off at the pass, you need not object that "sugar" (ha!
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ Enthalpy adds the product of pressure and specific volume, thus capturing the amount of energy transferred when something crosses a control boundary.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ These systems are open and are moved away from equilibrium by the fluxes of material and energy across their boundary.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

That something can be the volumetric region surrounding a single atom resonating energy, such as Max Planck defined in 1900; it can be a body of steam or air in a steam engine, such as Sadi Carnot defined in 1824; it can be the body of a tropical cyclone, such as Kerry Emanuel theorized in 1986 in the field of atmospheric thermodynamics; it could also be just one nuclide (i.e. a system of quarks) as some are theorizing presently in quantum thermodynamics.
.For an engine, a fixed boundary means the piston is locked at its position; as such, a constant volume process occurs.^ All in all, scientists have been able to 'catalyze the fruit fly evolutionary process such that what has been seen to occur in (fruit fly) is the equivalent of many millions of years of normal mutations and evolution.'
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ This means that over all, the engine does a positive amount of work.

.In that same engine, a moveable boundary allows the piston to move in and out.^ Along the boundary between the closed system and the surroundings, the temperature may be different from the system temperature, allowing energy flow into or out of the system as it moves toward equilibrium.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Indeed, it is the very act of it spreading out that > > allows you to live at all, or for car engines to run.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ The values of q 1 and q 2 are the same as in the case of the engine, but the direction of flow is reversed and work is put into the system rather than being taken out.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.For closed systems, boundaries are real while for open system boundaries are often imaginary.^ The Earth, for example, is an open system, but might be considered closed if one neglected meteorites, space probes, etc.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Systems are divided into three categories: an isolated system can exchange neither matter nor energy with its surroundings, a closed system can exchange energy but not matter, and an open system can exchange both energy and matter.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Along the boundary between the closed system and the surroundings, the temperature may be different from the system temperature, allowing energy flow into or out of the system as it moves toward equilibrium.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

There are five dominant classes of systems:
  1. Isolated Systems – matter and energy may not cross the boundary
  2. Adiabatic Systems – heat must not cross the boundary
  3. Diathermic Systems - heat may cross boundary
  4. Closed Systems – matter may not cross the boundary
  5. Open Systems – heat, work, and matter may cross the boundary (often called a control volume in this case)
.As time passes in an isolated system, internal differences in the system tend to even out and pressures and temperatures tend to equalize, as do density differences.^ It includes the equivalence of heat and work, but is more general than that, in that there are many forms of energy that are interconvertible, but with the total for an isolated system remaining constant over time.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Isolated Systems An isolated system is one in which neither mass nor energy flows in or out.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ In summary, isolated systems always maintain constant total energy while tending toward maximum entropy, or disorder.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.A system in which all equalizing processes have gone practically to completion, is considered to be in a state of thermodynamic equilibrium.^ In this paper we have recast the second law of thermodynamics from the old statement of "entropy increase" into a statement that describes systems undergoing processes so that they will reach a unique state of equilibrium.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ One can follow the thermodynamics of irreversible processes to anaylze how the system as a whole approaches a state of equilibrium.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ In this context the second law mandates that as systems are moved away from equilibrium they will take advantage of all means available to them to resist externally applied gradients.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

.In thermodynamic equilibrium, a system's properties are, by definition, unchanging in time.^ In terms of our previous definition of entropy, this is equivalent to 1/ T 1 =1/ T 2 , which makes perfect sense since the systems are in thermal equilibrium.

^ We therefore conclude that, given the availability of energy and an appropriate coupling mechanism, the maintenance of a living system far from equilibrium presents no thermodynamic problems.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Thermodynamics does not do so well describing systems that are far from equilibrium.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.Systems in equilibrium are much simpler and easier to understand than systems which are not in equilibrium.^ Coupling the energy flow through the system to do the chemical and thermal entropy work is much easier than doing the configurational entropy work.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.Often, when analysing a thermodynamic process, it can be assumed that each intermediate state in the process is at equilibrium.^ Arity : 2 Domain : Control-volume Range : Steady-state-steady-flow-process Defined in theory: Thermodynamics Source code: thermodynamics.lisp .
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

^ One can follow the thermodynamics of irreversible processes to anaylze how the system as a whole approaches a state of equilibrium.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ A quantity function Instance-Of : Function , Quantity-function Arity : 2 Quantity-Function-Of : Steady-state-steady-flow-process Range : Everywhere-continuous-quantity Defined in theory: Thermodynamics No source file available.
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

This will also considerably simplify the situation. .Thermodynamic processes which develop so slowly as to allow each intermediate step to be an equilibrium state are said to be reversible processes.^ Prigogine has developed a more general formulation of the laws of thermodynamics which includes nonlinear, irreversible processes such as autocatalytic activity.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Arity : 2 Domain : Control-volume Range : Steady-state-steady-flow-process Defined in theory: Thermodynamics Source code: thermodynamics.lisp .
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

^ One can follow the thermodynamics of irreversible processes to anaylze how the system as a whole approaches a state of equilibrium.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

Conjugate variables

.The central concept of thermodynamics is that of energy, the ability to do work.^ The kinetic-theoretical concept equivalent to temperature in thermodynamics turns out to be the *kinetic* energy of particles (e.g.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ The idea is to drive forward the otherwise thermodynamically unfavorable polymerization reaction by allowing solar energy to flow through the aqueous system to do the necessary work.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Instance-Of : Physical-dimension Axioms: ( = Work-Dimension Energy-Dimension ) Defined in theory: Thermodynamics Source code: thermodynamics.lisp .
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

.By the First Law, the total energy of a system and its surroundings is conserved.^ The first law is the law of conservation of energy.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Indeed, the law of conservation of energy is also known as the first law of thermodynamics.

^ The first law of thermodynamics, also known as the law of conservation of energy, states that the total energy of any system remains the same, except to the extent it exchanges energy with its surroundings.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

.Energy may be transferred into a system by heating, compression, or addition of matter, and extracted from a system by cooling, expansion, or extraction of matter.^ Q for an amount of heat to be transferred into either system: .

^ Here the energy possessed by one part of the system, E 1 or E 2 , plays the same role as the variable R in the examples of free expansion above.

^ An attribute function Arity : 2 Attribute-Function-Of : Condensor-with-heat-transfer-system Defined in theory: Thermodynamics No source file available.
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

.In mechanics, for example, energy transfer equals the product of the force applied to a body and the resulting displacement.^ We can conclude that each atom in the solid, on average, has of energy in the electrical energy due to its x displacement along the x axis, and equal amounts for y and z .

^ Enthalpy adds the product of pressure and specific volume, thus capturing the amount of energy transferred when something crosses a control boundary.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The loss of thermal energy from the gas equals the work it does as it expands, and using the result of homework problem 2 on page 326, the work done in an infinitesimal expansion equals P d V , so .

.Conjugate variables are pairs of thermodynamic concepts, with the first being akin to a "force" applied to some thermodynamic system, the second being akin to the resulting "displacement," and the product of the two equalling the amount of energy transferred.^ You can apply thermodynamics to an "isolated system".
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ T = change in the logarithm of the number of quantum states divided by the change in the energy of the system, everything else being fixed.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Is your result consistent with the second law of thermodynamics?

The common conjugate variables are:

Instrumentation

There are two types of thermodynamic instruments, the meter and the reservoir. A thermodynamic meter is any device which measures any parameter of a thermodynamic system. .In some cases, the thermodynamic parameter is actually defined in terms of an idealized measuring instrument.^ Since their arguments do not work in terms of thermodynamics, some anti-evolutionists turn to information theory, which contains a quantity called entropy.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ Dalton) is applied to a thermodynamically macroscopic system, then, completeness requires that every macroscopic property have some description in the kinetic-theoretic terms as well.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ This is an important example because it allows us to show that our present microscopic treatment of thermodynamics is consistent with our previous macroscopic approach, in which temperature was defined in terms of an ideal gas thermometer.

.For example, the zeroth law states that if two bodies are in thermal equilibrium with a third body, they are also in thermal equilibrium with each other.^ There are two ways of stating the third law: .
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The zeroth law actually states that if two systems A and B are in equilibrium with each other, and systems B and C are also in equlibrium with each other, then systems A and C are also in equilibrium with each other.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ December 30, 2008 - 2:05pm Another way of stating the zeroth law?
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.This principle, as noted by James Maxwell in 1872, asserts that it is possible to measure temperature.^ If a principle that correlates the kinetic energy of a nanotube (say due to vibrations of the ionic cores and waves in the lattice gas) with something external can be discovered, then, even an experimental measurement of the temperature of the nanotube will be possible.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ As outlined in my notes on temperature , the above definition does lead to experimental procedure to measure temperature, as well as measure the number of quantum states.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.An idealized thermometer is a sample of an ideal gas at constant pressure.^ A simplified version of an ideal gas thermometer.

^ To show consistency with the macroscopic approach to thermodynamics, we need to show that these results are consistent with the behavior of an ideal-gas thermometer.

^ During this constant-volume reheating, we have PV = nkT , so the amount of pressure regained is a direct indication of how much the gas cooled down when it lost an amount of energy Δ E .

.From the ideal gas law pV=nRT, the volume of such a sample can be used as an indicator of temperature; in this manner it defines temperature.^ The volume of the noble gas gives an indication of temperature.

^ From the ideal gas law, the ratio of the pressures is the same as the ratio of the absolute temperatures, .

^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.Although pressure is defined mechanically, a pressure-measuring device, called a barometer may also be constructed from a sample of an ideal gas held at a constant temperature.^ Pressure is proportional to temperature when volume is held constant.

^ From the ideal gas law, the ratio of the pressures is the same as the ratio of the absolute temperatures, .

^ Although we can achieve as good an approximation to an ideal gas as we wish by making the pressure very low, it seems nevertheless that there should be some more fundamental way to define temperature.

.A calorimeter is a device which is used to measure and define the internal energy of a system.^ Most biochemistry texts give a good short intro on how biology systems are explained through the use of Free Energy.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Thermodynamics When you use energy, the rules are very well defined.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The entropy change for a system is defined mathematically as the flow of energy divided by the temperature, or, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.A thermodynamic reservoir is a system which is so large that it does not appreciably alter its state parameters when brought into contact with the test system.^ If we make they contact with a large system, this may destroy the states of the real systems and make them have the same temperature of the large system itself.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Thermodynamics, largely driven into being by the steam engine, should be pushed into a further mature stage, driven by the nanotechnology that controls matter on the atomic scale.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ A mere appeal to open system thermodynamics does little good.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.It is used to impose a particular value of a state parameter upon the system.^ However, when the energy of the system is held at a constant value U, the system becomes an isolated system, and has a certain number of quantum states Ω.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ [NOTE: this categorization is not universally used; in particular it is not uncommon to hear an isolated system as defined above described as closed.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

.For example, a pressure reservoir is a system at a particular pressure, which imposes that pressure upon any test system that it is mechanically connected to.^ In particular, one way to hold a small system at a fixed temperature is to allow it to exchange energy with a reservoir of energy.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ In particular, no external reservoir is necessary to define temperature of the system.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.The Earth's atmosphere is often used as a pressure reservoir.The reservoir is isolated with the nature.^ The Atmospheric Vortex Engine, which Mr. Michaud has patented, represents a reasonable attempt to copy what nature has achieved while accessing this reservoir.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Using this fact, we can find the variation of atmospheric pressure with altitude, assuming constant temperature: .

.It is important that these two types of instruments are distinct.^ Natural selection is a recognized principle of differential reproduction which presupposes the existence of at least two distinct types of self-replicating molecules.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.A meter does not perform its task accurately if it behaves like a reservoir of the state variable it is trying to measure.^ In this picture, one does not speak of the temperature of the system, but speaks of the fluctuation of the system among various quantum states.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Temperature, as well as any other thermodynamic state variable, an statistical mean (ensemble average) of certain thermodynamic measure.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ If there is a temperature for a nanoscale small system, then, measuring it or not, temperature should be an independent state variable.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.If, for example, a thermometer were to act as a temperature reservoir it would alter the temperature of the system being measured, and the reading would be incorrect.^ As discussed above , you can hold arbitrarily small system at a fixed temperature by letting the small system exchange energy with a heat reservoir.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ The reservoir is so large that, as the small system draws energy from the reservoir, the temperature of the reservoir remains unchanged.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Heat is being sucked in from the hot reservoir, and since the working gas is always in thermal equilibrium with the hot reservoir, its temperature is constant.

.Ideal meters have no effect on the state variables of the system they are measuring.^ If we make they contact with a large system, this may destroy the states of the real systems and make them have the same temperature of the large system itself.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ In this picture, one does not speak of the temperature of the system, but speaks of the fluctuation of the system among various quantum states.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ They are able to demonstrate mathematically that within a system that was initially homogeneous, one may subsequently have a periodic, spatial variation of concentration.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

States & processes

.When a system is at equilibrium under a given set of conditions, it is said to be in a definite state.^ We can readily see the difficulty in getting polymerization reactions to occur under equilibrium conditions, i.e., in the absence of such an energy flow.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ The Impossibility of Protein Formation under Equilibrium Conditions It was noted in Chapter 7 that because macromolecule formation (such as amino acids polymerizing to form protein) goes uphill energetically, work must be done on the system via energy flow through the system.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Under such conditions a state that would normally be highly improbable under equilibrium conditions can be maintained indefinitely.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.The thermodynamic state of the system can be described by a number of intensive variables and extensive variables.^ In this picture, one does not speak of the temperature of the system, but speaks of the fluctuation of the system among various quantum states.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ This definition makes it clear that temperature involves two distinct quantities: the energy of a system, and the number of quantum states of the system.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ T = change in the logarithm of the number of quantum states divided by the change in the energy of the system, everything else being fixed.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.The properties of the system can be described by an equation of state which specifies the relationship between these variables.^ The introduction of temperature is to describe the equilibrium state of two systems under thermal contact.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ In summary, equations 8-2c and 8-3c quantify the notion that only specified, aperiodic macromolecules are capable of carrying the large amounts of information characteristic of living systems.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ In these notes, I have deliberately treated the subject as an experimental science: all quantities must be measurable, including the number of quantum states of an isolated system.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.State may be thought of as the instantaneous quantitative description of a system with a set number of variables held constant.^ If we make they contact with a large system, this may destroy the states of the real systems and make them have the same temperature of the large system itself.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ The number of ways the mass of the linear system may be arranged ( c ) can be calculated using statistics.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ In this picture, one does not speak of the temperature of the system, but speaks of the fluctuation of the system among various quantum states.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.A thermodynamic process may be defined as the energetic evolution of a thermodynamic system proceeding from an initial state to a final state.^ Arity : 2 Domain : Thermal-cycle Range : Thermal-process Defined in theory: Thermodynamics Source code: thermodynamics.lisp .
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

^ A quantity function Instance-Of : Function , Quantity-function Arity : 2 Quantity-Function-Of : Thermal-process Range : Everywhere-continuous-quantity Defined in theory: Thermodynamics No source file available.
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

^ They are able to demonstrate mathematically that within a system that was initially homogeneous, one may subsequently have a periodic, spatial variation of concentration.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.Typically, each thermodynamic process is distinguished from other processes, in energetic character, according to what parameters, as temperature, pressure, or volume, etc., are held fixed.^ Pressure is proportional to temperature when volume is held constant.

^ The proportionality of volume to temperature at fixed pressure was the basis for our definition of temperature.

^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.Furthermore, it is useful to group these processes into pairs, in which each variable held constant is one member of a conjugate pair.^ The gas constant R = 1.9872 cal/deg-mole and T is assumed to be 298 o K. Substituting these values into eqs.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Using this fact, we can find the variation of atmospheric pressure with altitude, assuming constant temperature: .

^ One method for taming complexity is the conservation laws, since they tell us that certain things must remain constant regardless of what process is going on.

The seven most common thermodynamic processes are shown below:
  1. An isobaric process occurs at constant pressure.
  2. An isochoric process, or isometric/isovolumetric process, occurs at constant volume.
  3. An isothermal process occurs at a constant temperature.
  4. An adiabatic process occurs without loss or gain of energy by heat.
  5. An isentropic process (reversible adiabatic process) occurs at a constant entropy.
  6. An isenthalpic process occurs at a constant enthalpy.
  7. A steady state process occurs without a change in the internal energy of a system.

See also

Applied fields

Lists and timelines

Wikibooks

References

  1. ^ Oxford American Dictionary
  2. ^ Enrico Fermi (1956). Thermodynamics. Courier Dover Publications. pp. (ix). ISBN 048660361X. OCLC 54033021 230763036 54033021. http://books.google.com/books?id=VEZ1ljsT3IwC&printsec=frontcover&dq=thermodynamics&lr=&as_brr=0&sig=ACfU3U24MHXNw_T3n2dj1QHRnPKxNyX7-g#PPP11,M1. 
  3. ^ a b c Perrot, Pierre (1998). A to Z of Thermodynamics. Oxford University Press. ISBN 0-19-856552-6. OCLC 38073404 123283342 38073404. 
  4. ^ Clark, John, O.E. (2004). The Essential Dictionary of Science. Barnes & Noble Books. ISBN 0-7607-4616-8. OCLC 63473130 58732844 63473130. 
  5. ^ Clausius, Rudolf (1850). On the Motive Power of Heat, and on the Laws which can be deduced from it for the Theory of Heat. Poggendorff's Annalen der Physick, LXXIX (Dover Reprint). ISBN 0-486-59065-8. 
  6. ^ Van Ness, H.C. (1983) [1969]. Understanding Thermodynamics. Dover Publications, Inc.. ISBN 9780486632773. OCLC 8846081. 
  7. ^ Dugdale, J.S. (1998). Entropy and its Physical Meaning. Taylor and Francis. ISBN 0-7484-0569-0. OCLC 36457809. 
  8. ^ Smith, J.M.; Van Ness, H.C., Abbott, M.M. (2005). Introduction to Chemical Engineering Thermodynamics. McGraw Hill. ISBN 0-07-310445-0. OCLC 56491111. 
  9. ^ Haynie, Donald, T. (2001). Biological Thermodynamics. Cambridge University Press. ISBN 0-521-79549-4. OCLC 43993556. 
  10. ^ Partington, J.R. (1989). A Short History of Chemistry. Dover. OCLC 19353301. 
  11. ^ Kelvin, William T. (1849) "An Account of Carnot's Theory of the Motive Power of Heat - with Numerical Results Deduced from Regnault's Experiments on Steam." Transactions of the Edinburg Royal Society, XVI. January 2. Scanned Copy
  12. ^ Cengel, Yunus A.; Boles, Michael A. (2005). Thermodynamics - an Engineering Approach. McGraw-Hill. ISBN 0-07-310768-9. 
  13. ^ Gibbs, Willard (1993). The Scientific Papers of J. Willard Gibbs, Volume One: Thermodynamics. Ox Bow Press. ISBN 0-918024-77-3. OCLC 27974820. 
  14. ^ Lewis, Gilbert N.; Randall, Merle (1923). Thermodynamics and the Free Energy of Chemical Substances. McGraw-Hill Book Co. Inc.. 
  15. ^ Moran, Michael J. and Howard N. Shapiro, 2008. Fundamentals of Engineering Thermodynamics. 6th ed. Wiley and Sons: 16.

Further reading

  • Goldstein, Martin, and Inge F. (1993). The Refrigerator and the Universe. Harvard University Press. .ISBN 0-674-75325-9. OCLC 32826343.  A nontechnical introduction, good on historical and interpretive matters.
  • Kazakov, Andrei (July-August 2008).^ January 2010 December 2009 November 2009 October 2009 September 2009 August 2009 July 2009 June 2009 May 2009 April 2009 March 2009 February 2009 January 2009 December 2008 November 2008 October 2008 September 2008 August 2008 July 2008 June 2008 May 2008 April 2008 March 2008 February 2008 January 2008 December 2007 November 2007 October 2007 September 2007 August 2007 July 2007 June 2007 May 2007 April 2007 March 2007 February 2007 January 2007 December 2006 November 2006 October 2006 .
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    "Web Thermo Tables – an On-Line Version of the TRC Thermodynamic Tables". .Journal of Research of the National Institutes of Standards and Technology 113 (4): 209–220.^ I am now with the Physical and Chemical Properties Division of the National Institute of Standards and Technology in Boulder, Colorado.
    • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

    ^ Allan H. Harvey of the Physical and Chemical Properties Division (as of September 2000) of the National Institute of Standards and Technology (NIST) in Boulder, Colorado produced the following treatise on the Second Law of Thermodynamics (SLOT).
    • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

    ^ I am now with the Physical and Chemical Properties Division of the National Institute of Standards and Technology (NIST) in Boulder, Colorado.
    • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

    http://nvl-i.nist.gov/pub/nistpubs/jres/113/4/V113.N04.A03.pdf
    . 
The following titles are more technical:

External links


Quotes

Up to date as of January 14, 2010

From Wikiquote

.Thermodynamics is a branch of physics that studies the movement of energy and how energy instills movement.^ Now it’s not too difficult to see how the configurational and thermodynamic dispersals (and their associated notions of entropy) are simple physical implementations of the above mathematical result.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

^ So far we have focused our discussion on simple physical systems and how thermodynamic gradients drive self-organization.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ Thermodynamics has a great bearing on how we use energy in processes, but not much on where the energy actually comes from.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.More precisely, it studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale by analyzing the collective motion of their particles using statistics.^ The data was collected using TIMS surface temperature acquisition system.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ VERY VERY VERY...EXTENSIVE. Statistical Mechanics "...provies the connection between microscopic motion of individual atoms of matter and macroscopically observable properties such as temperature, pressure, entropy, free energy, heat capacity, chemical potential, viscosity, spectra, reaction rates, etc..."
  • Martindale's Calculators On-Line Center: Mechanical Engineering: S-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]
  • Martindale's Calculators On-Line Center: Chemistry Center: R-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

.19th century physicists defined three Laws of thermodynamics to sum up the basic principles of the subject; in the 20th century, an unofficial "zeroth law" was added.^ The total closed system is subject to the 2nd law of thermodynamics.
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

^ Basically, the Second Law of Thermodynamics is simple; it says that in every naturally occurring reaction, whatever is most probable (when all things are considered) is most likely to happen.
  • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

^ The first and second laws of thermodynamics have been well understood for well over a century, and the third for just over a century, but the subject is still viewed by most as being pretty arcane.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

Contents

Sourced

.
  • Isn’t thermodynamics considered a fine intellectual structure, bequeathed by past decades, whose every subtlety only experts in the art of handling Hamiltonians would be able to appreciate?^ Basically, the Second Law of Thermodynamics is simple; it says that in every naturally occurring reaction, whatever is most probable (when all things are considered) is most likely to happen.
    • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

    ^ If you looked at the Earth thermodynamically without considering current solar energy, you would come to the conclusion that we all must have died a while ago.
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ Every decade reveals mistakes of the past and it would be idiotic to imagine that this process has now stopped and nothing new will be discovered and no current theories will be overturned.
    • Thermodynamics 10 January 2010 17:12 UTC mwillett.org [Source type: Original source]

    .
    • Pierre Perrot, "A to Z Dictionary of Thermodynamics"
  • Thermodynamics is a funny subject.^ Thermodynamics is a funny subject .
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    ^ "Thermodynamics is a funny subject.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    .The first time you go through it, you don't understand it at all.^ Do you have a specific position on this or are you going to change it all the time?
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    ^ The first time you go through the subject you don't understand it at all.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    ^ There a ton of evidence, and more coming in all the time you just somehow ignore it.
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    .The second time you go through it, you think you understand it, except for one or two small points.^ I think I am in the stage of second time .
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    ^ The second time you go through it, you think you do understand it, except for one or two small points.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    ^ The first time you go through the subject you don't understand it at all.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    .The third time you go through it, you know you don't understand it, but by that time you are so used to it, it doesn't bother you any more.^ There a ton of evidence, and more coming in all the time you just somehow ignore it.
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    ^ If you don't understand the details of the "theory of everything" you link to, do you have any business promoting it?
    • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ If you don't think you have been "blithely skipping along" without taking responsibility for your words (which I asked you to do several times), then what exactly do you think you have been doing?
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    .
  • Nothing in life is certain except death, taxes and the second law of thermodynamics.^ The Second Law of Thermodynamics devastates this theory.

    ^ Violation of the second law of thermodynamics?
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    ^ The second law of thermodynamics requires, .
    • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

    .All three are processes in which useful or accessible forms of some quantity, such as energy or money, are transformed into useless, inaccessible forms of the same quantity.^ Once it stops, all its kinetic energy has been transformed into heat.

    ^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    ^ The need to define thermodynamic temperature, the meaning of auxiliary thermodynamic functions, the origin, usefulness and use of partial molar quantities are all examined.
    • thermodynamics - Lulu.com 10 January 2010 17:12 UTC www.lulu.com [Source type: General]

    .That is not to say that these three processes don't have fringe benefits: taxes pay for roads and schools; the second law of thermodynamics drives cars, computers and metabolism; and death, at the very least, opens up tenured faculty positions.^ The Second Law of Thermodynamics devastates this theory.

    ^ The second law of thermodynamics requires, .
    • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

    ^ This is one statement of the Second Law of Thermodynamics .
    • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

    .
  • The law that entropy always increases holds, I think, the supreme position among the laws of Nature.^ Another statement of the 2nd law is that, for any isolated system, the entropy remains the same during any reversible process and increases during any irreversible process.
    • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

    ^ I don't like to think of entropy or the second law of thermodynamics as relating to anything other than irreversibilities in work/heat producing processes.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    ^ Natural processes are accompanied by an increase in the entropy of the universe [Clausius-Kelvin statement].
    • IoHT :: 110+ Variations of the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.humanthermodynamics.com [Source type: Academic]

    .If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations — then so much the worse for Maxwell's equations.^ Thanks for pointing out your concerns.
    • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ If someone tries to sell you a heat engine for which an efficiency better than the efficiency of a Carnot engine is claimed, stay not on the order of your leaving, but depart immediately.
    • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

    ^ However, what do you think would happen if man could figure out everything about nature and conform it to a universal formula.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    .If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes.^ If it is found to be contradicted by observation -- well, these experimentalists do bungle things sometimes.
    • Human and natural systems oppose the second law of thermodynamics byimporting inputs for replacement and maintenance 11 January 2010 21:25 UTC www.dieoff.org [Source type: Original source]

    ^ The nice thing about all these observations is you don't have to believe anybody about them, you can go check for yourself.
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    .But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.^ Is your result consistent with the second law of thermodynamics?

    ^ The Second Law of Thermodynamics devastates this theory.

    ^ Violation of the second law of thermodynamics?
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    .
  • A good many times I have been present at gatherings of people who, by the standards of the traditional culture, are thought highly educated and who have with considerable gusto been expressing their incredulity at the illiteracy of scientists.^ MANY LAWS There are many, many laws operating in the natural world.

    ^ A similar case could be given for the notion of “wave”: there are physical waves (e.g., of electromagnetic nature), natural waves in the macro-world (sound waves, water waves), but even “social waves”, such as waves of fashion and of culture.
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    ^ Sir Arthur Eddington (1882-1944) was a leading British astronomer of the first half of the 20th century.

    .Once or twice I have been provoked and have asked the company how many of them could describe the Second Law of Thermodynamics.^ Does the Second Law describe what WILL happen?
    • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

    ^ The Second Law of Thermodynamics devastates this theory.

    ^ Violation of the second law of thermodynamics?
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    The response was cold: it was also negative. .
    • C. P. Snow, 1959 Rede Lecture entitled "The Two Cultures and the Scientific Revolution".
  • The second law of thermodynamics is, without a doubt, one of the most perfect laws in physics.^ One more comment about thermodynamic equation in second law.
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ The Second Law of Thermodynamics devastates this theory.

    ^ Violation of the second law of thermodynamics?
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    .Any reproducible violation of it, however small, would bring the discoverer great riches as well as a trip to Stockholm.^ The Big Bang would also somehow violate this law as well but I think the most serious problem for this theory is the horizon problem.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    ^ In the case of a small system in contact with a heat reservoir, however, we do have a well defined way to characterize the system: the Boltzmann distribution.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    .The world’s energy problems would be solved at one stroke.^ At a macroscopic level it’s often useful to model energy by the quantity of an abstract “substance” (e.g., “temperature”), because this allows us to solve conveniently problems about objects and processes in the macro-world.
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    ^ In 2002, this was more energy in one hour than the world used in one year."
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ If we could convey to the average folks that ONE LAW, that humanity does not and CANNOT make energy, we can only move it to where we can use it, we would have accomplished so much.
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    .It is not possible to find any other law (except, perhaps, for super selection rules such as charge conservation) for which a proposed violation would bring more skepticism than this one.^ Some forms of energy are more convenient than others in certain situations.

    ^ After a few weeks of growth, the animal will be much larger and more complex, since it began with one cell and ends up with more than a trillion cells.
    • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

    ^ I don't like to think of entropy or the second law of thermodynamics as relating to anything other than irreversibilities in work/heat producing processes.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    .Not even Maxwell’s laws of electricity or Newton’s law of gravitation are so sacrosanct, for each has measurable corrections coming from quantum effects or general relativity.^ Einstein, if I recall correctly, questioned Newton's gravitational laws by pointing out that physical characteristics -- such as mass, length, and time -- that scientists had used to quantify this mechanistic universe were relative and not absolute.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    ^ Examples of Intuition: Everyday and Thermodynamic • As you'll see in the following examples, much of the astronomical evolution of our universe is just particles "doing what comes naturally" when they feel the effect of a force: electrical, gravitational, or nuclear.
    • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

    ^ But after Newton’s era we learned that they are implementations of the same fundamental law, the law of gravitational attraction.
    • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

    .The law has caught the attention of poets and philosophers and has been called the greatest scientific achievement of the nineteenth century.^ We should focus our attention on these scientifically important questions instead of wasting time on unwarranted criticisms that claim the Second Law as justification.
    • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

    Engels disliked it, for it supported opposition to Dialectical Materialism, while Pope Pius XII regarded it as proving the existence of a higher being. .
  • A theory is the more impressive the greater the simplicity of its premises, the more different kinds of things it relates, and the more extended its area of applicability.^ "[A law] is more impressive the greater is the simplicity of its premises, the more different are the kinds of things it relates, and the more extended its range of applicability.

    ^ "Bertalanffy (1968) calved the relation between irreversible thermodynamics and information theory one of the most fundamental unsolved problems in biology.

    ^ Evolution teaches that matter and living things keep becoming more complex, end continually evolve toward greater perfection.

    .Therefore the deep impression that classical thermodynamics made upon me.^ Therefore, the deep impression which classical thermodynamics made on me.

    .It is the only physical theory of universal content which I am convinced will never be overthrown, within the framework of applicability of its basic concepts.^ It is the only physical theory of universal content which I am convinced, that within the framework of applicability of its basic concepts will never be overthrown."

    ^ The basic test, I would suppose, is that in drawing theoretical parallels between two theories describing the same sphere of physical phenomena, if the two concepts go on to produce exactly the same physical effects, then, within the scope of the comparison, the two concepts should be regarded as equivalent--on the grounds that their "valence" (or capacity to produce effects) was equal.
    • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

    ^ If the 2nd law is to be applicable at all in this context, we must be able to make the rigorous definitions of information content required by the theory.
    • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

    .
    • Albert Einstein (author), Paul Arthur, Schilpp (editor).^ Albert Einstein said that it is the premier law of all science; Sir Arthur Eddington referred to it as the supreme metaphysical law of the entire universe."

      Autobiographical Notes. A Centennial Edition. Open Court Publishing Company. 1979. p. 31 [As quoted by Don Howard, John Stachel. Einstein: The Formative Years, 1879-1909 (Einstein Studies, vol. 8). Birkhäuser Boston. 2000. p. 1]

Unsourced

  • Every mathematician knows it is impossible to understand an elementary course in thermodynamics.
    • V.I. Arnold

Humor

.
  • In this house, we obey the laws of thermodynamics!^ In this house, we obey the laws of thermodynamics!
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ Libelle on December 30, 2008 - 11:00pm The title of this post should have been "In this house we do not ignore the laws of thermodynamics".
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ December 31, 2008 - 3:58am The title of this post should have been "In this house we do not ignore the laws of thermodynamics".
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    .
  • S happens.^ And this perpetual motion machine she made today is a joke!
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ This has all happened while population and non-energy inputs have also increased.
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    .
    • Bumper sticker on the second law of thermodynamics.
  • How does bear know about thermodynamics?^ The second law of thermodynamics requires, .
    • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

    ^ This is one statement of the Second Law of Thermodynamics .
    • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

    ^ Discussion with a Creationist about the Second Law of Thermodynamics Discussion with a Creationist about the Second Law of Thermodynamics .
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    .
    • Image macro showing a bear eating apples, after one showing a bear trying to get at apples frozen in ice.
  • Zeroth: You must play the game.^ For a moment, pretend that you are playing a game of Hearts.
    • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]


    First: You can't win.
    .Second: You can't break even.^ You can only break even on a very cold day.
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]


    Third: You can't quit the game.
    • A common scientific joke expressing the laws of thermodynamics.
      • Variant:
        .You can't win; you can only break even.^ You can only break even on a very cold day.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

        ^ Later, in your discussion of Entropy you conclude with the statement that “you can only break even on a very cold day”--and that furthermore that, “it never gets that cold”, referring to absolute zero being a hopelessly unachievable target.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]


        .You can only break even at absolute zero.^ You can only break even on a very cold day.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

        ^ Later, in your discussion of Entropy you conclude with the statement that “you can only break even on a very cold day”--and that furthermore that, “it never gets that cold”, referring to absolute zero being a hopelessly unachievable target.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]


        .You can't reach absolute zero.^ It impossible to reach absolute zero in a finite number of steps.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

      • Another variant:
        .Zeroth: You must play the game.^ You must play the game.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

        ^ December 31, 2008 - 11:29am Maybe the rule should read, " The game must be played.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

        ^ Because "I" or "you" will stop playing the game when we're dead, though the game will continue to be played with our remains.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]


        First: You can't win.
        .Second: You can't break even, except on a very cold day.^ You can only break even on a very cold day.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

        ^ The second time you go through it, you think you do understand it, except for one or two small points.
        • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

        ^ Later, in your discussion of Entropy you conclude with the statement that “you can only break even on a very cold day”--and that furthermore that, “it never gets that cold”, referring to absolute zero being a hopelessly unachievable target.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]


        Third: It doesn't get that cold.
      • Yet another variant:
        Zeroth: There is a game.
        First: You can't win.
        Second: You must lose.
        Third: You can't quit.
      • An old US undergraduate version of the previous variant concludes:
        .Second: You can't break even – except at absolute zero.^ You can only break even on a very cold day.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

        ^ The second time you go through it, you think you do understand it, except for one or two small points.
        • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

        ^ Later, in your discussion of Entropy you conclude with the statement that “you can only break even on a very cold day”--and that furthermore that, “it never gets that cold”, referring to absolute zero being a hopelessly unachievable target.
        • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]


        .Third: You can't get to absolute zero.^ The third law of thermodynamics (page 318) The entropy of a system approaches zero as its temperature approaches absolute zero.

        ^ The third law concerns changes in entropy as the temperature approaches absolute zero, and indirectly can be used to show the impossibility of attaining absolute zero.
        • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

        .
  • It’s the Second Law of Thermodynamics: Sooner or later everything turns to shit.^ The clue is in the name: second law of THERMODYNAMICS. Not the second law of everything.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    ^ AM The clue is in the name: second law of THERMODYNAMICS. Not the second law of everything.
    • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

    ^ The second law of thermodynamics requires, .
    • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

  • Murphy's Law about Thermodynamics: Things get worse under pressure.
  • If you think things are in a mess now, JUST WAIT! (unknown)

Other

  • A common scientific joke, as stated by C. P. Snow, expresses the four laws simply and surprisingly accurately as:
Zeroth: "You must play the game."
First: "You can't win."
Second: "You can't break even."
Third: "You can't quit the game."
.
  • The parody rapper MC Hawking makes several references to the Second Law in his songs, usually in references to creationist claims about the Second Law.^ Discussion with a Creationist about the Second Law of Thermodynamics Discussion with a Creationist about the Second Law of Thermodynamics .
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    ^ One more comment about thermodynamic equation in second law.
    • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

    ^ I find it amazing that you could write so much about the second law at .
    • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

    In his song "Entropy", he makes a reference to the C.P. Snow joke above: "You can't win, you can't break even, you can't leave the game".
  • "Old Chemists never die: they reach thermodynamical equilibrium" (unknown).

External links

Wikipedia
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Study guide

Up to date as of January 14, 2010

From Wikiversity

Merge-arrows.svg
A merger has been proposed.
.It has been suggested that this resource or section be merged with Thermodynamics and Equilibrium (Discuss).^ An open system offers an additional possibility for ordering---that of maintaining a system far from equilibrium via mass flow through the system, as will be discussed in the next section.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

."Thermodynamics" comes from the greek words "therme" which means heat and "dynamikos" which means force,power.^ It was Clausius who first defined the quantity entropy and coined the word (from a Greek word meaning transformation).
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

.So "Thermodynamics" is essentially the study of forces due to heat or heat due to forces.^ VERY VERY VERY...EXTENSIVE. Thermodynamics "...Thermodynamics is essentially the study of the internal motions of many body systems.
  • Martindale's Calculators On-Line Center: Mechanical Engineering: S-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]
  • Martindale's Calculators On-Line Center: Chemistry Center: R-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

.It deals with the conversion of energies in terms of heat and mechanical work and their relationship with properties of the system.^ Work and heat are not properties of the system, but they are rather subtle concepts.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ Mechanical work can be turned into heat.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ I work in energy systems.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.The field of engineering science, which deals with the applications of thermodynamics and its laws to work producing and work absorbing devices, in order to understand their functions and improve their performance, is known as Thermal Engineering.^ If they do, then the laws do not work or the other sciences.
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

^ Thermodynamics is an exact science which deals with energy.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ So, having heard the proper description, the learner will see an order-to-disorder progression and no contradiction with the 2nd law of thermodynamics.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

.An understanding of the common terminology would be very useful before going further.^ If the hot-side temperature can be lowered (say, by using the condenser to pre-heat the domestic hot water supply) the CoP can go up even further.
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

^ August 3, 2007 - 4:25pm And yet, going from 2 to 3 inches (5 to 7.5 cm) of insulation would help a lot without using up a lot of space...
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The long answer involves me going to a lab and synthesizing a really complicated molecule from very simple molecules using U.V light, heat, and inorganic reagents.
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

Terminology:
System: The region of interest for the purpose study.
Boundary: An imaginary line that encompasses the region of interest.
.Heat: Energy transfer due to temperature difference.^ Along the boundary between the closed system and the surroundings, the temperature may be different from the system temperature, allowing energy flow into or out of the system as it moves toward equilibrium.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ The distinction between heat and work is essentially a practical one; increase in kinetic energy affects the temperature of the system, while increase in potential energy affects the internal energy and work of the system.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

^ The term Q i represents the i -th heat term associated with the transfer of energy into the control volume; the term Q e represents the e -th heat term representing energy leaving the control volume.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

.Work: Energy transfer due to movement.^ Conservation of energy therefore tells us that work done by the gas must be exactly balanced by the amount of heat transferred in from the reservoir.

^ Where Q is heat transfer in calories and T is in degrees Kelvin [2] Exergy/Availability: A measure of available work content of energy.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ The state of the material objects by means of which this energy is transferred as work is completely organized.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

.Temperature: Temperature is a property which measures the degree of hotness or coldness of body.^ T L is the temperature of the cold reservoir and T H is the temperature of the hot reservoir.

^ The cold flux is then moved to a compressor, and is compressed to hotter than the house temperature, the cold flux not hot, contributes heat to the house!
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

^ An isentropic refrigerator with a cold-side temperature of 4°C (277 K) and a hot-side temperature of 35°C (308 K) will reject (308/277) joules for every joule of heat it takes up.
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

This is due to molecular vibration.

Principal laws of Thermodynamics

  • Zeroeth law of thermodynamics states that if two objects are each in thermal equilibrium with a third, then they are also in thermal equilibrium with each other.
  • The first law of thermodynamics states that energy can be neither created nor destoyed.
  • The second law of thermodynamics states that dq=tds.
  • The third law of thermodynamics states that at absolute zero (the lowest possible temperature), there is no moleclular movement.
Further reading :

Introduction to Thermodynamics

.Now let's see the chapters we will cover in what can be called an "Introduction to Thermodynamics" as a University course.^ Let us see a couple of explanations for the second law of thermodynamics that have been given, which ignore the dispersion theorem and the deeper relation between thermodynamic and configurational entropy.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

^ "The authors see the second law of thermodynamics as man's description of the prior and continuing work of a Creator, who also holds the answer to the future destiny of man and the universe."

^ Now it’s not too difficult to see how the configurational and thermodynamic dispersals (and their associated notions of entropy) are simple physical implementations of the above mathematical result.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

Here we are:

Wikibooks


1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

THERMODYNAMICS (from Gr. .6Epµ5s, hot, 81lva.us, force).^ Epµ5s, hot, 81lva.us, force).

^ This tells us that we can use work to force heat to flow from cold to hot and we can convert heat to useful work.
  • PES 100: Thermodynamics 10 January 2010 17:12 UTC www.uccs.edu [Source type: Original source]

.I. The name thermodynamics is given to that branch of the general science of Energetics which deals with the relations between thermal and mechanical energy, and the transformations of heat into work, and vice versa.^ The converse process of the transformation of heat into mechanical work or other forms of energy is subject to limitations.

^ Heat cannot be completely transformed into work.
  • ECONOMY AND THERMODYNAMICS 10 January 2010 17:12 UTC www.ecen.com [Source type: FILTERED WITH BAYES]

^ I. The name thermodynamics is given to that branch of the general science of Energetics which deals with the relations between thermal and mechanical energy, and the transformations of heat into work, and vice versa.

.Other transformations of heat are often included under the same title (see Energetics).^ Other transformations of heat are often included under the same title (see Energetics ).

^ Specific heat under other conditions.

^ Study of the laws governing the transformation of heat energy to and from other forms of energy, thus of the efficient design and working of heat engines (such as the gas engine and the steam engine).

.An historical account of the development of thermodynamics is given in the article Heat.^ An historical account of the development of thermodynamics is given in the article Heat.

^ Students in this course develop a mathematical and physical understanding of the fundamental concepts and principles of classical thermodynamics including properties, state determination, work and heat transfer.
  • Texas Tech University :: Mechanical Engineering :: ME 2322 Engineering Thermodynamics I 11 January 2010 21:25 UTC www.me.ttu.edu [Source type: Academic]

^ The relation between heat and energy was important for the development of steam engines, and in 1824 Sadi Carnot had captured some of the ideas of thermodynamics in his discussion of the efficiency of an idealized engine.
  • Historical Notes: History of thermodynamics 10 January 2010 17:12 UTC www.wolframscience.com [Source type: FILTERED WITH BAYES]

.The object of the present article is to illustrate the practical application of the two general principles - (I) Joule's law of the equivalence of heat and work, and (2) Carnot's principle, that the efficiency of a reversible engine depends only on the temperatures between which it works; these principles are commonly known as the first and second laws of thermodynamics.^ Reversible and irreversible processes, the second law of thermodynamics.
  • Subject Sylbus: thermodynamics - 084213 10 January 2010 17:12 UTC techmvs.technion.ac.il [Source type: Academic]

^ Second Law of Thermodynamics - second statement .
  • Laws of Thermodynamics 11 January 2010 21:25 UTC physics.csustan.edu [Source type: FILTERED WITH BAYES]

^ E is a reversible heat engine and R an infinite heat reservoir.
  • Second law of thermodynamics - encyclopedia article - Citizendium 11 January 2010 21:25 UTC en.citizendium.org [Source type: Academic]

.The application will necessarily be confined to simple cases such as are commonly met with in practice, or are required for reference in cognate subjects.^ The application will necessarily be confined to simple cases such as are commonly met with in practice, or are required for reference in cognate subjects.

^ A perfectly adequate response to such nonsense is to point out that the earth is not an isolated system, and therefore the condition required by the Second Law is not met.
  • Creationism and the Laws of Thermodynamics | NCSE 10 January 2010 17:12 UTC ncse.com [Source type: Academic]

^ Modeling of exsolution and related phenomena such as critical points requires a better model for the free energy of phases than the simple one implemented by the demonstration applet.
  • Phase Equilibria Glossary 11 January 2010 21:25 UTC www.gps.caltech.edu [Source type: Reference]

.2. Application of the First Law.^ The first law is the application of conservation of energy to the system, and the second sets limits on the possible efficiency of the machine and determines the direction of energy flow.

^ Preface Introduction Thermodynamic Systems Zeroth Law First Law Second Law Third Law Applications Appendix Further Reading [ edit ] Related books .
  • Engineering Thermodynamics - Wikibooks, collection of open-content textbooks 10 January 2010 17:12 UTC en.wikibooks.org [Source type: Reference]

^ However, no information about the direction of the process can be obtained by the application of the first law.
  • Second Law of Thermodynamics - Engineers Edge 11 January 2010 21:25 UTC www.engineersedge.com [Source type: Reference]

- .The complete transformation of mechanical energy into heat by friction, or some analogous process of degradation, is always possible, and is made the basis of experiments for the determination of the mechanical equivalent of the heat unit (see Calorimetry).^ The converse process of the transformation of heat into mechanical work or other forms of energy is subject to limitations.

^ Mechanical Equivalent of Heat 70.
  • THERMODYNAMICS 10 January 2010 17:12 UTC www.wesleyan.edu [Source type: Academic]

^ Some of the available energy is always dissipated in nonrecoverable friction or heat energy.
  • Second Law Of Thermodynamics (SLOT) and its Application to Evolution 11 January 2010 21:25 UTC www.tektonics.org [Source type: FILTERED WITH BAYES]

.The converse process of the transformation of heat into mechanical work or other forms of energy is subject to limitations.^ The converse process of the transformation of heat into mechanical work or other forms of energy is subject to limitations.

^ Heat cannot be completely transformed into work.
  • ECONOMY AND THERMODYNAMICS 10 January 2010 17:12 UTC www.ecen.com [Source type: FILTERED WITH BAYES]

^ During the conversion process, all the energy that enters a conversion device is turned into other forms of energy.
  • Energy Rules! Energy Conversion and the Laws of Thermodynamics - Energy Conversion Introduction 10 January 2010 17:12 UTC www.uwsp.edu [Source type: FILTERED WITH BAYES]

.When a quantity of heat, H, is supplied to a body, part is expended in raising the temperature of the body, or in expanding the volume against molecular forces, and is represented by an increase in the total quantity of energy contained in the body, which is generally called its Intrinsic Energy, and will be denoted by the symbol E. The remainder is equivalent to the external work, W, done by the body in expanding or otherwise, which can be utilized for mechanical purposes, and ceases to exist as heat in the body.^ The total kinetic energy is an extensive quantity.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ From energy conservation this work would generate heat and lead to an increase of entropy .
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

^ The total energy a body contains as a result of the positions and motions of its molecules is called its internal energy; in general, a body's temperature is a direct measure of its internal energy.
  • thermodynamics Facts, information, pictures | Encyclopedia.com articles about thermodynamics 10 January 2010 17:12 UTC www.encyclopedia.com [Source type: Academic]

.The application of the first law leads immediately to the equation, II=E - E,+W, . (I) in which E 0 represents the quantity of energy originally present in the body, and all the quantities are supposed, as usual, to be expressed in mechanical units.^ The First Law of Thermodynamics (conservation of energy) .

^ Energy agrees with the first law of thermodynamics?
  • WikiAnswers - What is the process that satisfies the first law of thermodynamics but violates the second law 11 January 2010 21:25 UTC wiki.answers.com [Source type: General]

^ The First Law is also stated as energy is conserved .
  • Laws of Thermodynamics - Cryogenic Information Library - Technifab Products, Inc. 10 January 2010 17:12 UTC www.technifab.com [Source type: FILTERED WITH BAYES]

.This equation is generally true for any series of transformations, provided that we regard H and W as representing the algebraic sums of all the quantities of heat supplied to, and of work done by the body, heat taken from the body or work done on the body being reckoned negative in the summation.^ Heat energy is transformed into work energy.
  • The second law of thermodynamics - Total equilibrium and heat engines. 11 January 2010 21:25 UTC www.flyingturtle.org [Source type: Original source]

^ Energy: The ability to do work or supply heat.
  • College Chemistry: Thermodynamics 10 January 2010 17:12 UTC www.chemistry24.com [Source type: FILTERED WITH BAYES]
  • Teach Chemistry: Thermodynamics 10 January 2010 17:12 UTC www.chemistry24.com [Source type: FILTERED WITH BAYES]

^ And this is true for EVERYTHING in general, the universe all over."
  • SECOND LAW OF THERMODYNAMICS - Does this basic law of nature prevent Evolution? - ChristianAnswers.Net 10 January 2010 17:12 UTC www.christiananswers.net [Source type: FILTERED WITH BAYES]

.E - E 0 , then, represents the total increase of the intrinsic energy of the body in its final state, which may be determined by measuring H and W. If after any series or cycle of transformations the body is restored to its initial state, we must have E=E 0 , whence it follows that H= W. But this simple relation is only true of the net balances of heat and work in a complete cyclical process, which must be adopted for theoretical purposes if we wish to eliminate the unknown changes of intrinsic energy.^ Heat cannot be completely transformed into work.
  • ECONOMY AND THERMODYNAMICS 10 January 2010 17:12 UTC www.ecen.com [Source type: FILTERED WITH BAYES]

^ Heat, work and internal energy: the concept of a function of state.
  • Stephen Blundell's homepage 10 January 2010 17:12 UTC users.ox.ac.uk [Source type: Academic]

^ That is, no device transfers its heat energy completely into work.
  • Physics 20: Thermodynamics 10 January 2010 17:12 UTC www.sasked.gov.sk.ca [Source type: FILTERED WITH BAYES]

.The balance of work obtainable in such a cycle depends on the limits of temperature in a manner which forms the subject of the second law.^ It is the second law that prohibits such engines.
  • Demons, Engines and the Second Law 11 January 2010 21:25 UTC www.aeiveos.com [Source type: Original source]

^ Second law of thermodynamics and the Carnot cycle .
  • AME Undergraduate Courses 10 January 2010 17:12 UTC www.nd.edu [Source type: Reference]

^ Needless to say, such a cycle contradicts the second law of thermodynamics.
  • BIASED THERMAL MOTION AND THE SECOND LAW OF THERMODYNAMICS 11 January 2010 21:25 UTC wbabin.net [Source type: FILTERED WITH BAYES]

3. Indicator or p.v. Diagram

.The significance of relation (I) is best appreciated by considering the graphic representation of quantities of heat and energy on a work-diagram.^ Thermodynamics The effects of work, heat and energy on a system Related Documents .

^ Heat energy is transformed into work energy.
  • The second law of thermodynamics - Total equilibrium and heat engines. 11 January 2010 21:25 UTC www.flyingturtle.org [Source type: Original source]

^ Energy: The ability to do work or supply heat.
  • College Chemistry: Thermodynamics 10 January 2010 17:12 UTC www.chemistry24.com [Source type: FILTERED WITH BAYES]
  • SAT Chemistry: Thermodynamics 10 January 2010 17:12 UTC www.rapidlearningcenter.com [Source type: Academic]
  • Teach Chemistry: Thermodynamics 10 January 2010 17:12 UTC www.chemistry24.com [Source type: FILTERED WITH BAYES]

HCl. HBr. HI. HNO,
HC103 H BrO,
137400 cal. 1 375 00 „ 136800 „ 136800 „ 137600 „ 137800 „
.On the familiar indicator diagram the state of the working substance is represented by the position of a point called the " statepoint," defined by the values of the pressure p and volume v of unit mass, as ordinate and abscissa respectively (fig.^ Density - Density ( ) is defined as mass per unit volume.

^ P and V are the pressure and volume of the system, respectively.
  • Thermodynamics - Chemistry Encyclopedia - reaction, gas, number, equation 11 January 2010 21:25 UTC www.chemistryexplained.com [Source type: Academic]

^ The state of a substance may be defined by means of the temperature and entropy as co-ordinates, instead of employing the pressure and volume as in the indicator diagram.

I). .Any line (" path " or " graph ") on the diagram, such as BCD, represents an " operation " or " process " i.e. a continuous series of states through which the substance may be made to pass in any transformation.^ Path - The series of states a system passes through during a process.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ Shape of polytropic-process lines on the h - s diagram.
  • The Design of Gas Turbine Engines-Thermodynamics and Aerodynamics-2nd Ed: CD ROM & DVD - CD-ROM 11 January 2010 21:25 UTC catalog.asme.org [Source type: Academic]

^ A device such as a refrigerator or air conditioner, designed to remove heat from a cold region and transfer it to a hot region, is essentially a heat engine operating in reverse, as the following energy flow diagram shows: A refrigerator, consisting of a fluid pumped through a closed system, involves a four-step process.
  • Heat engines and the second law 11 January 2010 21:25 UTC physics.bu.edu [Source type: FILTERED WITH BAYES]

.It is tacitly assumed that the motion is relatively so slow that the pressure and temperature of the substance are practically uniform throughout its mass at any stage of the process.^ It is tacitly assumed that the motion is relatively so slow that the pressure and temperature of the substance are practically uniform throughout its mass at any stage of the process.

^ Substances describable by temperature and pressure alone .
  • Thermodynamics - Biocrawler, the free encyclopedia 10 January 2010 17:12 UTC www.biocrawler.com [Source type: Academic]

^ The following graphs show the changes in pressure, velocity and temperature of the gas as it passes through the various stages of a jet engine.
  • Thermodynamics 10 January 2010 17:12 UTC www.eng.fsu.edu [Source type: Academic]

.Otherwise the transformation could not be fully represented on the diagram, and would not be reversible.^ Otherwise the transformation could not be fully represented on the diagram, and would not be reversible.

^ Molecules could briefly extract energy from their surroundings, combining in ways that would otherwise be impossible in practice.
  • Law of Thermodynamics Faces Repeal - WSJ.com 11 January 2010 21:25 UTC online.wsj.com [Source type: General]

^ That is, the system would stay at the temperatures of the reservoirs during those heat transfers - necessary for the process to be reversible since the heat flow could not be reversed to go from the lower to the higher temperature.
  • SECOND LAW 11 January 2010 21:25 UTC www.calpoly.edu [Source type: Original source]

.The area BCDdb under the path represents the external work done by the substance in expanding from B to D, which is analytically represented by the integral of pdv taken along the given path.^ It is given by the area under the PV graph .
  • First Law of Thermodynamics 10 January 2010 17:12 UTC tutors4you.com [Source type: Reference]

^ In each case, the work done is the area under the curve.
  • Physics: The Laws of Thermodynamics - CliffsNotes 11 January 2010 21:25 UTC www.cliffsnotes.com [Source type: FILTERED WITH BAYES]

^ The area BCDdb under the path represents the external work done by the substance in expanding from B to D, which is analytically represented by the integral of pdv taken along the given path.

.Any closed path or figure, such as ABCD, represents a complete cycle or series of operations, in the course of which the substance is restored to its original state with respect to temperature, intrinsic energy and other properties.^ One such variable of state is temperature.
  • Second Law of Thermodynamics - SkepticWiki 11 January 2010 21:25 UTC www.skepticwiki.org [Source type: Original source]

^ Thus, temperature has this property that energy does not have.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Any closed path or figure, such as ABCD, represents a complete cycle or series of operations, in the course of which the substance is restored to its original state with respect to temperature, intrinsic energy and other properties.

.The area DABbd under the return path (v diminishing) represents work done on the substance, or against the back-pressure, and is negative.^ In each case, the work done is the area under the curve.
  • Physics: The Laws of Thermodynamics - CliffsNotes 11 January 2010 21:25 UTC www.cliffsnotes.com [Source type: FILTERED WITH BAYES]

^ Recall that the work is the negative of the area under the curve.
  • Introduction to the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.chem.arizona.edu [Source type: Original source]

^ For this segment, work is done by the piston on the gas , which is represented by the area under the C–D segment of the curve from V 3 to V 4 .
  • Physics: The Laws of Thermodynamics - CliffsNotes 11 January 2010 21:25 UTC www.cliffsnotes.com [Source type: FILTERED WITH BAYES]

.The area of the cycle, viz., that enclosed by the path Bcda, represents the balance of external work done by the substance in one cycle, and is positive if the cycle is described clockwise 0' O as indicated by the arrows.^ The work is the area of the enclosed region on the graph.
  • Heat engines and the second law 11 January 2010 21:25 UTC physics.bu.edu [Source type: FILTERED WITH BAYES]

^ One of the cycles is the reversible path, and is so labelled.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ The area of the cycle, viz., that enclosed by the path Bcda , represents the balance of external work done by the substance in one cycle, and is positive if the cycle is described clockwise 0' O as indicated by the arrows.

.The simplest types of process or operation are: (I), heating or cooling at constant volume, represented by vertical lines such as Bb, called Isometrics, in which the pressure varies, but no ex ternal work is done.^ We can rewrite this expression for a process at constant volume as .

^ Specific Heat at constant Volume .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ Practice Problem 1: Which of the following processes are run at constant volume and which are run at constant pressure?
  • Energy, Enthalpy, and the First Law ofThermodynamics 10 January 2010 17:12 UTC chemed.chem.purdue.edu [Source type: Academic]

.(2) Heating or cooling at constant pressure, represented by horizontal lines such as NA, called Isopiestics, in which the external work done is the product of the pressure p and the expansion v" - v'. (3) Expansion or compression at constant temperature, represented by curves called Isothermals, such as BC, AD, the form of which depends on the nature of the working sub stance.^ For the isothermal expansion I drew temperature on the y-axis and volume on the x-axis, and drew a line of constant temperature in the increasing x-direction.
  • Thermodynamics Questions 10 January 2010 17:12 UTC www.physicsforums.com [Source type: FILTERED WITH BAYES]

^ The potential used depends on the constraints of the system, such as constant temperature or pressure.
  • Thermodynamics - encyclopedia article - Citizendium 10 January 2010 17:12 UTC reid.citizendium.org [Source type: Academic]
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]
  • Thermodynamics 10 January 2010 17:12 UTC pustakalaya.olenepal.org [Source type: Reference]

^ Constant pressure expansion/compression work.
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

.The isothermals are approximately equilateral hyperbolas (pv= constant), with the axes of p and v for asymptotes, for a gas or unsaturated vapour, but coincide with the isopiestics for a saturated vapour in presence of its liquid.^ The isothermals are approximately equilateral hyperbolas ( pv= constant), with the axes of p and v for asymptotes, for a gas or unsaturated vapour, but coincide with the isopiestics for a saturated vapour in presence of its liquid.

^ During this constant-volume reheating, we have PV = nkT , so the amount of pressure regained is a direct indication of how much the gas cooled down when it lost an amount of energy Δ E .

^ Path 1a: isothermal expansion of gas from A = 3 bar, 1 L to B = 1 bar, 3 L against constant P ext of 1 bar.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.(4) Expansion or compression under the condition of heat-insulation, represented by curves called Adiabatics, such as BAZ or CDZ', which are necessarily steeper than the isothermals.^ The adiabatic curve has a more negative slope than the isothermal curve.

^ (This is analogous to insulated compression or expansion of a heat engine; in general, a compression or expansion of this type, with no transfer of heat, is called adiabatic .

^ Expansion or compression under the condition of heat-insulation, represented by curves called Adiabatics, such as BAZ or CDZ', which are necessarily steeper than the isothermals.

.A cycle such as ABCD enclosed by parts of two isothermals, BC, AD, and two adiabatics, AB, CD, is the simplest form of cycle for theoretical purposes, since all the heat absorbed, H', is taken in during the process represented by one isothermal at the temperature o', and all the heat rejected, H", is given out during the process represented by the other at the temperature 0". This is the cycle employed by Carnot for the establishment of his fundamental principle of reversibility as the criterion of perfect efficiency in a heat engine.^ E is a reversible heat engine and R an infinite heat reservoir.
  • Second law of thermodynamics - encyclopedia article - Citizendium 11 January 2010 21:25 UTC en.citizendium.org [Source type: Academic]

^ Efficiency of a heat engine .
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.chem1.com [Source type: FILTERED WITH BAYES]

^ Since the two isotherms are joined by two adiabats, it can be shown that .
  • Chemical thermodynamics 11 January 2010 21:25 UTC guweb2.gonzaga.edu [Source type: Academic]

.The area ABCD, representing the work, W, per cycle, is the difference (H' - H") of the quantities of heat absorbed and rejected at the temperatures 0 and 0". As the temperature 0" is lowered, the area of the cycle increases, but since W can never exceed H', there must be a zero limit of temperature at which the pressure would vanish and the area of the cycle become equal to the whole heat absorbed at the higher temperature.^ Heat will flow only from material at higher temperature to material at a lower temperature.
  • Contractor School Online® - Contractor Glossary of Terms 11 January 2010 21:25 UTC www.contractorreferral.com [Source type: Reference]

^ But if there is a temperature difference, some of the heat will be used to raise the temperature of the heat sink .
  • The Second Law of Thermodynamics 10 January 2010 17:12 UTC www.bluffton.edu [Source type: FILTERED WITH BAYES]

^ Heat can be turned into mechanical work, but there are limitations.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.Taking this ideal limit as a theoretical or absolute zero, the value of
H
may be represented on the diagram by the whole area included between the two adiabatics BAZ, CDZ' down to the points where they intersect the isothermal of absolute zero, or the zero isopiestic OV asymptotically at infinity.^ Two of the processes are isothermal and two are adiabatic.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ Taking this ideal limit as a theoretical or absolute zero, the value of H may be represented on the diagram by the whole area included between the two adiabatics BAZ, CDZ' down to the points where they intersect the isothermal of absolute zero, or the zero isopiestic OV asymptotically at infinity.

^ If the substance in any state such as B were allowed to expand adiabatically ( dH = o ) down to the absolute zero, at which point it contains no heat and exerts no pressure, the whole of its available heat energy might theoretically be recovered in the form of external work, represented on the diagram by the whole area BAZcb under the adiabatic through the state-point B, bounded by the isometric Bb and the zero isopiestic bV. The change of the intrinsic energy in passing from one state to another, as from B to C is represented by the addition of the heat-area H= Bczz ', and the subtraction of the work-area W = BCcb.

.If the substance in any state such as B were allowed to expand adiabatically (dH = o) down to the absolute zero, at which point it contains no heat and exerts no pressure, the whole of its available heat energy might theoretically be recovered in the form of external work, represented on the diagram by the whole area BAZcb under the adiabatic through the state-point B, bounded by the isometric Bb and the zero isopiestic bV. The change of the intrinsic energy in passing from one state to another, as from B to C is represented by the addition of the heat-area H= Bczz', and the subtraction of the work-area W = BCcb. It follows from the first law that the intrinsic energy of a substance in a given state must always be the same, or that the change of E in any transformation must depend only on the initial and final states, and not on the path or process.^ If energy always exists, one can always use it.
  • HEAT and THE THREE LAWS OF THERMODYNAMICS 11 January 2010 21:25 UTC www.josephnewman.com [Source type: Original source]

^ The converse process of the transformation of heat into mechanical work or other forms of energy is subject to limitations.

^ It is given by the area under the PV graph .
  • First Law of Thermodynamics 10 January 2010 17:12 UTC tutors4you.com [Source type: Reference]

.It will be observed that the areas representing H and W both depend on the form of the path BC, but that the difference of the areas representing the change of intrinsic energy dE is independent of BC, which is a boundary common to both H and W. This is mathematically expressed by the statement that dE is an exact differential of a function of the co-ordinates defining the state of the body, which can be integrated between limits without reference to the relation representing the path along which the variations are taken.^ Michael, the puzzle can be expressed without reference to coarse states.
  • Overcoming Bias : Scandalous Heat 10 January 2010 17:12 UTC www.overcomingbias.com [Source type: Original source]

^ It is a mathematical requirement that state variables have Exact differentials .
  • Phase Equilibria Glossary 11 January 2010 21:25 UTC www.gps.caltech.edu [Source type: Reference]

^ Q is the incremental energy state change / increase .
  • Second Law Of Thermodynamics (SLOT) and its Application to Evolution 11 January 2010 21:25 UTC www.tektonics.org [Source type: FILTERED WITH BAYES]

Missing image
Thermodynamics-1.jpg
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Thermodynamics-2.jpg
d Volume
.4. Application of Carnot's Principle.^ Application of Carnot's Principle.

- .Carnot
adopted as the analytical expression of his principle the statement that the efficiency W/H, or the work obtainable per unit of heat by means of a perfect engine taking in heat at a temperature C. and rejecting heat at o° C., must be some function F(t) of the temperature t, the lower limit o° C. being supposed constant.^ Efficiency of a heat engine .
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.chem1.com [Source type: FILTERED WITH BAYES]

^ F(T 2 ,T 1 ) F is some as yet unknown function (an algebraic expression) of the two temperatures.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ This makes the engine less efficient that a Carnot engine, because heat is being discharged at a temperature that is not as cool as the environment.

.He was unable to XXV.I. 26 a apply the principle directly in this form, as it would require an exact knowledge of the properties of substances through a wide range of temperature.^ He was unable to XXV.I. 26 a apply the principle directly in this form, as it would require an exact knowledge of the properties of substances through a wide range of temperature.

^ We will return to phase transformations later, but let's now see why these phases form in the first place and why each one is stable over such a wide range of temperatures.
  • Thermodynamics 10 January 2010 17:12 UTC www.tulane.edu [Source type: Reference]

^ "In its most modern forms, the Second Law is considered to have an extremely wide range of validity.
  • SCIENTISTS SPEAK ABOUT LAWS OF NATURE VS EVOLUTION - 1 11 January 2010 21:25 UTC www.pathlights.com [Source type: Original source]

.He therefore employed the corresponding expression for a cycle of infinitesimal range dt at the temperature t in which the work dW obtainable from a quantity of heat H would be represented by the equation dW =HF'(t)dt, where F'(t) is the derived function of F(t), or dF(t)/dt, and represents the work obtainable per unit of heat per degree fall of temperature at a temperature t. The principle in this form is readily applicable to all cases, and is independent of any view with regard to the nature of the heat.^ Net work per unit mass flow in a Brayton cycle 6 .
  • II THE SECOND LAW OF THERMODYNAMICS 11 January 2010 21:25 UTC web.mit.edu [Source type: Reference]

^ What does work in a cycle correspond to on a P-V diagram?
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

^ It is natural to confuse heat with temperature.

.It simply asserts that the efficiency function F'(t), which is known as Carnot's function, is the same for all substances at the same temperature.^ It simply asserts that the efficiency function F'(t), which is known as Carnot's function, is the same for all substances at the same temperature.

^ That is, they will all have the same temperature.

^ The fourth law of thermodynamics says that if two objects are both at the same temperature as a third, then all three are at the same temperature - they are said to be at a thermal equilibrium.

.Carnot verified this by calculating the values of F'(t) at various temperatures from the known properties of vapours and gases, and showed that the efficiency function diminished with rise of temperature, as measured on the scale of the mercury or gas thermometer, from about 1.40 kilogrammetres per kilo-calorie per degree C. at o° C. to about I 11 at Ioo° C., according to the imperfect data available in his time.^ Thermodynamic Temperature Scale - A temperature scale that is independent of the properties of the substances that are used to measure temperature.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ Temperatures measured on this scale are designated as degrees Fahrenheit (° F) .
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

^ It simply asserts that the efficiency function F'(t), which is known as Carnot's function, is the same for all substances at the same temperature.

Applying the above equation to a gas obeying the law pv=RT, for which the work done in isothermal expansion from a volume i to a volume r is W=RT loger, whence dW=R log e rdt, he deduced the expression for the heat absorbed by a gas in isothermal expansion H=R log er/F'(t). He also showed that the difference of the specific heats at constant pressure and volume, S - s, must be the same for equal volumes of all gases at the same temperature and pressure, being represented by the expression R/TF'(t). He remarks that ” the law according to which the motive power of heat varies at different points of the thermometric scale is intimately connected with that of the variations of the specific heats of gases at different temperatures - a law which experiment has not yet made known to us with sufficient exactness." If he had ventured to assume the difference of the specific heats constant, it would have followed that F'(t) must vary inversely as T. The same result follows if the work W =RT log e ?' done by a gas in isothermal expansion is assumed to be equivalent or proportional to the heat absorbed, H=R log e r/F'(t). .Mayer (1842) made this assumption in calculating the mechanical equivalent of heat.^ In the calculation the following assumptions are made: 1.
  • Heaven is Hotter than Hell 10 January 2010 17:12 UTC www.lhup.edu [Source type: FILTERED WITH BAYES]

^ Mechanical Equivalent of Heat 70.
  • THERMODYNAMICS 10 January 2010 17:12 UTC www.wesleyan.edu [Source type: Reference]

^ Mechanical equivalent of heat .
  • Thermodynamics is the Connection Between Heat and Work - Succeed in Understanding Physics: School for Champions 10 January 2010 17:12 UTC www.school-for-champions.com [Source type: FILTERED WITH BAYES]

.Joule (1845) was the first to prove it approximately by direct experiment, but did not see his way to reconcile Carnot's principle, as stated by Clapeyron, with the mechanical theory.^ See a textbook for more details on  G and  G°´ - we will see this later on at transition state theory References 1.
  • Introductory biological thermodynamics 10 January 2010 17:12 UTC www.slideshare.net [Source type: Academic]

^ Langton's conclusion is that the 'Carnot Principle' based on the Caloric theory, allowed for the possibility of perpetual motion machines of the second kind.

^ Clausius, who first stated the principle of Carnot in a manner consistent with the true theory of heat, expresses this law as follows: - It is impossible for a self-acting machine, unaided by any external agency, to convey heat from one body to another at a higher temperature.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tim-thompson.com [Source type: Original source]

.Holtzmann (1845) by the same assumption deduced the value J/T for the function F'(t), but obtained erroneous results by combining this assumption with the caloric theory.^ Holtzmann (1845) by the same assumption deduced the value J/T for the function F'(t), but obtained erroneous results by combining this assumption with the caloric theory.

^ Carnot's result was remarkably arrived at using the erroneous concept that heat is an indestructible substance, that is, the caloric theory of heat .
  • Sample Chapter for Haddad, W.M., Chellaboina, V., Nersesov, S.G.: Thermodynamics: A Dynamical Systems Approach. 10 January 2010 17:12 UTC www.pupress.princeton.edu [Source type: Reference]

^ When necessary, results have been adjusted to units of mol dm -3 to obtain the numerical value(s) of K c given in these tables.
  • Thermodynamics of Enzyme-Catalyzed Reactions 10 January 2010 17:12 UTC xpdb.nist.gov [Source type: Academic]

.Clausius (1850), applying the same assumption, deduced the same value of F'(t), and showed that it was consistent with the mechanical theory and Joule's experiments, but required that a vapour like steam should deviate more considerably from the gaseous laws than was at that time generally admitted.^ Laws are expected to apply generally.
  • Jeff's Lunchbreak: Creation Museum/Creationist Rule of Thumb with the 2nd Law of Thermodynamics 11 January 2010 21:25 UTC www.jefflewis.net [Source type: Original source]

^ If the experiment unequivocally shows that their values differ, the second law is disproved.
  • BIASED THERMAL MOTION AND THE SECOND LAW OF THERMODYNAMICS 11 January 2010 21:25 UTC wbabin.net [Source type: FILTERED WITH BAYES]

^ What law is the same like the first law of thermodynamics?
  • WikiAnswers - What is the process that satisfies the first law of thermodynamics but violates the second law 11 January 2010 21:25 UTC wiki.answers.com [Source type: General]

.The values of F'(t) calculated previously by Sir W. Thomson (Lord Kelvin) from Regnault's tables of the properties of steam, assuming the gaseous laws, did not vary exactly as J/T. Joule's experiments on the equivalence of W and H were not sufficiently precise to decide the question.^ The values of F'(t) calculated previously by Sir W. Thomson (Lord Kelvin) from Regnault's tables of the properties of steam, assuming the gaseous laws, did not vary exactly as J/T. Joule's experiments on the equivalence of W and H were not sufficiently precise to decide the question.

^ First Law; steam tables .

^ Henri-Victor Regnault shows that gas behavior doesn't quite follow Boyle's law at low temperatures and extrapolates a value of -273°C for absolute zero.  Joule and Kelvin shows that expanding gases become cooler in the process.  .
  • Sketching the History of Statistical Mechanics and Thermodynamics 11 January 2010 21:25 UTC omega.math.albany.edu:8008 [Source type: Academic]

.This most fundamental point was finally settled by a more delicate test, devised by Lord Kelvin, and carried out in conjunction with Joule (1854), which showed that the fundamental assumption W =H in isothermal expansion was very nearly true for permanent gases, and that F'(t) must therefore vary very nearly as J/T. Kelvin had previously proposed to define an absolute scale of temperature independent of the properties of any particular substance in terms of Carnot's function by making F'(t) constant.^ Thermodynamic Temperature Scale - A temperature scale that is independent of the properties of the substances that are used to measure temperature.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ This most fundamental point was finally settled by a more delicate test, devised by Lord Kelvin, and carried out in conjunction with Joule (1854), which showed that the fundamental assumption W =H in isothermal expansion was very nearly true for permanent gases, and that F'(t) must therefore vary very nearly as J/T. Kelvin had previously proposed to define an absolute scale of temperature independent of the properties of any particular substance in terms of Carnot's function by making F'(t) constant.

^ Therefore, the accumulation term must be zero.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

.He now proposed to define absolute temperature as proportional to the reciprocal of Carnot's function, so as to agree as closely as possible with the scale of the gas thermometer.^ Kelvin Scale - An absolute thermodynamic temperature scale first proposed by Lord Kelvin.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ Carnot's theorem lays the basis for the absolute temperature scale.
  • JHT :: The Second Law of Thermodynamics and the Evolution of Living Systems 11 January 2010 21:25 UTC www.humanthermodynamics.com [Source type: Academic]

^ What will happen to the gas at absolute zero temperature (0 K)?
  • Ask the Experts: Thermodynamics 10 January 2010 17:12 UTC www.physlink.com [Source type: FILTERED WITH BAYES]

.With this definition of temperature 0, if the heat H is measured in work units, the expression of Carnot's principle for an infinitesimal cycle of range do reduces to the simple form dW/d9=H/0. Combining this with the first law, for a Carnot cycle of finite range, if H is the heat taken in at 0', and H" is the heat rejected at 0", the work W done in the cycle is equal to the difference H' - H", and we have the simple relations, W/(0' - o") =H'/o' =H" o". .^ The converse process of the transformation of heat into mechanical work or other forms of energy is subject to limitations.

^ In this cycle, a fluid (called a refrigerant) in super-heated vapor form flows through a pipe and into a compressor where it is compressed into a hotter gas with a higher pressure.
  • Apologetics Press - God and the Laws of Thermodynamics: A Mechanical Engineer�s Perspective 10 January 2010 17:12 UTC www.apologeticspress.org [Source type: Original source]

^ It is a set of theories that correlate macroscopic properties that we can measure (such as temperature, volume, and pressure) to energy and its capability to deliver work.
  • ENGINEERING.com > Thermodynamics 11 January 2010 21:25 UTC www.engineering.com [Source type: Reference]

(2) 5. Thermodynamical Relations. - .The most important and most useful of the relations between the thermodynamical properties of a substance may be very simply deduced from a consideration of the indicator diagram by a geometrical method, which is in many respects more instructive than the analytical method generally employed.^ Thermodynamic Temperature Scale - A temperature scale that is independent of the properties of the substances that are used to measure temperature.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ The most important and most useful of the relations between the thermodynamical properties of a substance may be very simply deduced from a consideration of the indicator diagram by a geometrical method, which is in many respects more instructive than the analytical method generally employed.

^ I. The name thermodynamics is given to that branch of the general science of Energetics which deals with the relations between thermal and mechanical energy, and the transformations of heat into work, and vice versa.

Referring to fig. .2, let BC be a small portion of any isothermal corresponding to the temperature
0', and AD a neighbouring isothermal 0". Let BE be an isometric through B meeting AD in E, and EC an isopiestic through E meeting BC in C. Let BA, CD be adiabatics through B and C meeting the isothermal 0" in A and D. Then by relations (2) the heat, H, absorbed in the isothermal change BC, is to the work, W, done in the cycle ABCD in the ratio of o
to (o' - o").^ This added heat changed the temperature of the band.

^ Q a /T a = Q r /T r where Q a is the heat added at the temperature T a , and Q r is the heat removed at the temperature T r , the difference between Q a and Q r is the work delivered by the ideal cycle.
  • "Tracing the Second Law", Feature Article, July 2007 11 January 2010 21:25 UTC www.memagazine.org [Source type: FILTERED WITH BAYES]

^ Heat engines - Isothermal and adiabatic processes .
  • thermodynamics -- Britannica Online Encyclopedia 10 January 2010 17:12 UTC www.britannica.com [Source type: Reference]

If the difference N Isopies `som et7„,l8 FIG. I.
of temperature .(o' - o") is small, the figure ABCD may be regarded as a parallelogram, and its area W as equal to the rectangle BE XEC. This is accurately true in the limit when (0' - 0") is infinitesimal, but in practice it is necessary to measure specific heats, &c., over finite ranges of temperature, and the error involved is generally negligible if the range does not exceed a few degrees.^ The latter involve a few degrees of freedom.
  • http://staff.science.uva.nl/~nieuwenh/QL2L.html 11 January 2010 21:25 UTC staff.science.uva.nl [Source type: Academic]

^ A heat pump may have an efficiency of 300% - for a small temperature gradient.
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Since there was no heat flow from the ball itself, there was no decrease in entropy from that subsystem (ie, the ball) and the overall entropy is equal to heat of impact divided by the absolute temperature of the surroundings (assuming, of course, that the small amount of heat generated did not change the temperature of the surroundings) There is no increase in entropy until the ball strikes the ground.
  • A Brief Review of Thermodynamics 11 January 2010 21:25 UTC www.fsteiger.com [Source type: Original source]

.BE is the increase of pressure (p' - p") produced by the rise of temperature (o' - o") if the volume is kept constant.^ It is a set of theories that correlate macroscopic properties that we can measure (such as temperature, volume, and pressure) to energy and its capability to deliver work.
  • ENGINEERING.com > Thermodynamics 11 January 2010 21:25 UTC www.engineering.com [Source type: Reference]

^ The problem with rising temperatures with elevation, and erroneous constant humidity, is a double deviation from the actual observations!
  • Niche Modeling » Greenhouse Thermodynamics and GCMs 10 January 2010 17:12 UTC landshape.org [Source type: FILTERED WITH BAYES]

^ At 373.14 K (99.99°C), the boiling point of water is reached at atmospheric pressure, and further additions of heat begin to boil off some of the water at this constant temperature.
  • Entropy - A Basic Understanding : International site for Spirax Sarco 11 January 2010 21:25 UTC www.spiraxsarco.com [Source type: FILTERED WITH BAYES]

.EC is the expansion (v" - v') produced by the same rise of temperature if the pressure is kept constant.^ EC is the expansion ( v" - v' ) produced by the same rise of temperature if the pressure is kept constant.

^ This constant is independent of the starting concentrations and will always be the same at constant temperature and pressure.

^ It would do away with the well-developed mathematical relationships of physical chemistry, including the effect of temperature and pressure on equilibrium constants and phase changes.
  • Second Law of Thermodynamics 10 January 2010 17:12 UTC www.fsteiger.com [Source type: FILTERED WITH BAYES]
  • Does evolution violate the second law of thermodynamics? 10 January 2010 17:12 UTC www.takeonit.com [Source type: Original source]
  • The Second Law of Thermodynamics, Evolution, and Probability 11 January 2010 21:25 UTC www.talkorigins.org [Source type: Reference]
  • - Thermodynamics vs. Evolutionism - 11 January 2010 21:25 UTC www.trueorigin.org [Source type: Original source]
  • A Brief Review of Thermodynamics 11 January 2010 21:25 UTC www.fsteiger.com [Source type: Original source]

.Substituting these symbols in the expression for the area, the relation becomes H=o(p' - p„)(v„_v')/(o' - o").^ "We hope that these seemingly mysterious relations become clearer by reading through this book."
  • The Second Law of Thermodynamics. by Brig Klyce 10 January 2010 17:12 UTC www.panspermia.org [Source type: FILTERED WITH BAYES]

^ Substituting these symbols in the expression for the area, the relation becomes H=o(p' - p„)(v„_v')/(o' - o").

.
.(3) This relation may be interpreted in two ways, according as we require the heat absorbed in terms of the change of pressure or volume.^ This relation may be interpreted in two ways, according as we require the heat absorbed in terms of the change of pressure or volume.

^ Similarly with pressure and volume; these cannot be precisely defined for a changing system because not every particle in the system is 'aware' of their current value, and certain areas of the system may behave as though the system has different pressure and volume.
  • Basic thermodynamics - Wikiversity 10 January 2010 17:12 UTC en.wikiversity.org [Source type: Academic]

^ The most direct example is the work term PdV , where pressure P (force per area) plays the role of generalized force and infinitesimal change of volume dV plays the role of displacement ( dV can, indeed, be effected by the infinitesimal displacement of a wall of a container).
  • Thermodynamics - encyclopedia article - Citizendium 10 January 2010 17:12 UTC reid.citizendium.org [Source type: Academic]

.(I) The heat, H, absorbed in isothermal expansion (latent heat of expansion) from p to p" is equal to the diminution of pressure (p' - p”) multiplied by the absolute temperature and by the expansion per degree (v" - v')/(o' - o") at constant pressure.^ The change in entropy is equal to the change in the heat along a reversible path divided by the temperature.
  • The Second Law of Thermodynamics states that the universe tends toward high entropy. If so, what happens when there is nothing left to be disordered? How can matter be constant? 11 January 2010 21:25 UTC www.physlink.com [Source type: Original source]

^ Units (Temperature; Pressure; Denstiy; Energy; Velocity; Viscosity; Surface Tension); Type of Data (Isothermal Properties; Isobaric Properties; Isochoric Properties; Saturation Properties)..."
  • Martindale's Calculators On-Line Center: Chemistry Center: R-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

^ The dimensions of molar entropy are energy per absolute temperature and number of moles [SI unit: joule/(K·mole)].
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

.(2) The heat,
H, absorbed in isothermal expansion from v
to v" is equal to the increase of volume (v" - v') multiplied by the absolute temperature, and by the increase of pressure per degree (p' - p")/(o' - o"), at constant volume.^ The model defines the equations needed to calculate the molar volume , enthalpy and Gibbs free energy , based on the temperature T , pressure p and component properties.

^ Specific Heat at constant Volume .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ Units (Temperature; Pressure; Denstiy; Energy; Velocity; Viscosity; Surface Tension); Type of Data (Isothermal Properties; Isobaric Properties; Isochoric Properties; Saturation Properties)..."
  • Martindale's Calculators On-Line Center: Chemistry Center: R-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

.In the notation of the calculus the relations become - dH/dp (0 const) = odv /do (p const) (4) dH/dv (0 const) =odp/do (v const) The negative sign is prefixed to dH/dp because absorption of heat +dH corresponds to diminution of pressure - dp. The utility of these relations results from the circumstance that the pressure and expansion co efficients are familiar and easily measured, whereas the latent heat of expansion is difficult to determine.^ The utility of these relations results from the circumstance that the pressure and expansion co efficients are familiar and easily measured, whereas the latent heat of expansion is difficult to determine.

^ In the notation of the calculus the relations become - dH/dp (0 const) = odv /do ( p const) (4) dH/dv (0 const) =odp/do ( v const) The negative sign is prefixed to dH/dp because absorption of heat +dH corresponds to diminution of pressure - dp.

^ Because the pressure increases during compression, the work of compression must be determined by the calculus integral: compression work = PdV where: P = pressure V = volume dV = the small change in volume taking place at the corresponding pressure P The integral sign indicates the summation of all the individual values of PdV. The equation relating temperature, pressure, and volume of an ideal gas is: PV = RT (2) where: P = pressure V = volume T = absolute temperature R = a constant which depends only on the amount of gas present In the case of a reversible, isothermal compression of an ideal gas we may substitute P from equation (2) into the equation for compression work.
  • The Second Law of Thermodynamics, Evolution, and Probability 11 January 2010 21:25 UTC www.talkorigins.org [Source type: Reference]

.The most instructive example of the application of relations (I) and (2) is afforded by the change of state of a substance at constant temperature and pressure.^ The most instructive example of the application of relations (I) and (2) is afforded by the change of state of a substance at constant temperature and pressure.

^ Substances describable by temperature and pressure alone .
  • Thermodynamics - Biocrawler, the free encyclopedia 10 January 2010 17:12 UTC www.biocrawler.com [Source type: Academic]

^ Further the change of aggregation state occurs at constant temperature, so that .
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

.Starting with unit mass of the substance in the first state (e.g.^ Starting with unit mass of the substance in the first state (e.g.

^ If we take unit mass of the substance at B, fig.

^ If J', J" represent the values of the function for unit mass of the substance of specific volumes v' and v" in the two states at temperature 0 and pressure and if a mass m is in the state v', and 1-m in the.

liquid) possessing volume .v at a tern-, perature 0" and pressure p" represented by the point A in fig.^ This function may be represented, for each state or phase of the system considered, by an area on the indicator diagram similar to that representing the intrinsic energy, E. The product 94, may be represented at any point such as D in Fig.

^ On the familiar indicator diagram the state of the working substance is represented by the position of a point called the " statepoint," defined by the values of the pressure p and volume v of unit mass, as ordinate and abscissa respectively (fig.

.3, the heat absorbed in raising the temperature to 0' and the pressure to
p
without change of state may be written s' (o' - o"), where s' is the specific heat of the substance in the first state at saturation pressure.^ This added heat changed the temperature of the band.

^ Specific Heat at constant Pressure .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ Substances describable by temperature and pressure alone .
  • Thermodynamics - Biocrawler, the free encyclopedia 10 January 2010 17:12 UTC www.biocrawler.com [Source type: Academic]

.If now the substance in the state B is entirely converted at constant temperature and pressure into the second state (e.g.^ If now the substance in the state B is entirely converted at constant temperature and pressure into the second state (e.g.

^ Substances describable by temperature and pressure alone .
  • Thermodynamics - Biocrawler, the free encyclopedia 10 January 2010 17:12 UTC www.biocrawler.com [Source type: Academic]

^ It would do away with the well-developed mathematical relationships of physical chemistry, including the effect of temperature and pressure on equilibrium constants and phase changes.
  • Second Law of Thermodynamics 10 January 2010 17:12 UTC www.fsteiger.com [Source type: FILTERED WITH BAYES]
  • Does evolution violate the second law of thermodynamics? 10 January 2010 17:12 UTC www.takeonit.com [Source type: Original source]
  • The Second Law of Thermodynamics, Evolution, and Probability 11 January 2010 21:25 UTC www.talkorigins.org [Source type: Reference]
  • - Thermodynamics vs. Evolutionism - 11 January 2010 21:25 UTC www.trueorigin.org [Source type: Original source]
  • A Brief Review of Thermodynamics 11 January 2010 21:25 UTC www.fsteiger.com [Source type: Original source]

saturated vapour), in which it occupies a volume .v", the line BC represents the change of volume (v" - v').^ BC represents the change of volume (v" - v').

^ It is not necessary in this example that AB, CD should be adiabatics, because the change of volume BC is finite.

^ Basically, the “boundary” is simply an imaginary dotted line drawn around the volume of a something in which there is going to be a change in the internal energy of that something.
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

.The heat absorbed in this change is called the latent heat of change of state, and may be represented by the symbol L'. The substance is then cooled to the lower temperature 0" along the path CD, keeping it in the saturated state.^ This added heat changed the temperature of the band.

^ The heat absorbed in this change is called the latent heat of change of state, and may be represented by the symbol L'.

^ The substance is then cooled to the lower temperature 0" along the path CD, keeping it in the saturated state.

.The heat evolved in this process may be represented by s"(o' - o"), where s" is the specific heat of the substance in the second state at saturation pressure.^ Equations of state - Heat capacity and specific heat .
  • thermodynamics -- Britannica Online Encyclopedia 10 January 2010 17:12 UTC www.britannica.com [Source type: Reference]

^ He reasoned that in the chemical process, some of the energy from the system represented the energy free to do work, the rest of the energy was due simply to the heat required or generated.
  • Fuel Thermodynamics 10 January 2010 17:12 UTC chemcases.com [Source type: FILTERED WITH BAYES]

^ But the assumption is far from obvious for a system more complex than an ideal gas, or for states far from equilibrium, or for processes other than the simple exchange of heat and work.
  • OfficeRocker! : Fighting the second law of thermodynamics 11 January 2010 21:25 UTC blogs.msdn.com [Source type: General]

.Finally, the substance is reconverted into the first state at the temperature 0", completing the cycle by the abstraction of a quantity of heat By the application of the first law, the difference of the quantities of heat absorbed and evolved in the cycle must be equal to the work represented by the area of the cycle, which is equal to (p' - p") (v" - v') in the limit when the difference of pressure is small.^ Areas on the temperature-entropy or 0, 4, diagram represent quantities of heat in the same way as areas on the indicator diagram represent quantities of work.

^ Heat and Work are not state variables: they depend on path (see the First Law ).
  • Phase Equilibria Glossary 11 January 2010 21:25 UTC www.gps.caltech.edu [Source type: Reference]

^ In the Carnot cycle this difference in heat appears as useful mechanical work.
  • thermodynamics Facts, information, pictures | Encyclopedia.com articles about thermodynamics 10 January 2010 17:12 UTC www.encyclopedia.com [Source type: Academic]

.By the application of the second law, relations (2), the same work area is equal to (o' - o")L'lo'. Dividing by (0' - e"), and writing dp/do and dL/do for the limiting values of !the ratios (p' - p")/(o' - o") and (L' - L")/(o' - o"), we obtain the important relations s' - s"+dL/do= (v" - v')dp/do=L/o,..^ Some of the characteristics of coaching development and activity as related to the Second Law are listed below.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC coachsci.sdsu.edu [Source type: Academic]
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www-rohan.sdsu.edu [Source type: Academic]

^ The Second Law of Thermodynamics states that during any reaction the total useful energy in the universe (the energy that is useful for doing work) will decrease.
  • Evolution & Entropy - Second Law of Thermodynamics 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

^ Let us see a couple of explanations for the second law of thermodynamics that have been given, which ignore the dispersion theorem and the deeper relation between thermodynamic and configurational entropy.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

.
.(5) in which dp/do is the rate of change of pressure with temperature when the two states are in equilibrium.^ It would do away with the well-developed mathematical relationships of physical chemistry, including the effect of temperature and pressure on equilibrium constants and phase changes.
  • Second Law of Thermodynamics 10 January 2010 17:12 UTC www.fsteiger.com [Source type: FILTERED WITH BAYES]
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  • The Second Law of Thermodynamics, Evolution, and Probability 11 January 2010 21:25 UTC www.talkorigins.org [Source type: Reference]
  • - Thermodynamics vs. Evolutionism - 11 January 2010 21:25 UTC www.trueorigin.org [Source type: Original source]
  • A Brief Review of Thermodynamics 11 January 2010 21:25 UTC www.fsteiger.com [Source type: Original source]

^ To compute the system’s change in energy, take it from its first to its second state, divide each infinitesimal amount of heat by the temperature that’s absorbed by the system, and add all the quantities.
  • Skeptic Friends Network - 2nd Law of Thermodynamics Argument Weak on Both Sides 11 January 2010 21:25 UTC www.skepticfriends.org [Source type: Original source]

^ Most systems near thermodynamic equilibrium can be described pretty well by the normal macroscopic measures such as temperature, volume and pressure.
  • Ralph Dumain: "The Autodidact Project": Shaun Lovejoy: "Christopher Caudwell and the Second Law of Thermodynamics" 11 January 2010 21:25 UTC www.autodidactproject.org [Source type: FILTERED WITH BAYES]

.It is not necessary in this example that AB, CD should be adiabatics, because the change of volume BC is finite.^ It is not necessary in this example that AB, CD should be adiabatics, because the change of volume BC is finite.

^ Recall the case of an adiabatic free expansion -- the temperature does not change at all, no work is done, but the volume increases.
  • UNIFIED ENGINEERING Thermodynamics Chapter 7 11 January 2010 21:25 UTC ocw.mit.edu [Source type: Academic]

^ Liquid gallium is used in the nanothermometer because the gallium volume changes linearly with temperature - rising up and down the tube - at a consistent rate when the tube was exposed to different temperatures.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.The same equations apply to the case of fusion of a solid, if L is the latest heat of fusion, and v', s', v", s" the specific volumes and specific heats of the solid and liquid respectively.^ Specific Heat at constant Volume .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ The same equations apply to the case of fusion of a solid, if L is the latest heat of fusion, and v', s', v", s" the specific volumes and specific heats of the solid and liquid respectively.

^ For solids and liquids, we see that the difference in the specific heats is small, and γ is about 1.0.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

.6. Ratio and Difference of Specific Heats.^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ He also showed that the difference of the specific heats at constant pressure and volume, S - s, must be the same for equal volumes of all gases at the same temperature and pressure, being represented by the expression R/TF'(t).

^ These results for the difference and the ratio of the specific heats at constant pressure and constant volume are very important and useful.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

- .If
we take unit mass of the substance at B, fig.^ If we take unit mass of the substance at B, fig.

^ The Specific Heat Capacity is the amount of heat required to change a unit mass of a substance by one degree in temperature .

^ The total entropy of the system is found by multiplying the entropy per unit mass of the substance in each state by the mass existing in that state, and adding the products so obtained.

.2, and cool it at constant volume to E, through an interval of temperature (o' - o"), the amount of heat abstracted may be written h = s (o' - 0"), where s is the specific heat at constant volume. If, starting from E, the same amount of heat h is restored at constant pressure, we should arrive at the point F on the adiabatic through B, since the substance has been transformed from B to F by a reversible path without loss or gain of heat on the whole.^ Specific Heat at constant Volume .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ An adiabatic process occurs without loss or gain of heat.
  • Thermodynamics - encyclopedia article - Citizendium 10 January 2010 17:12 UTC reid.citizendium.org [Source type: Academic]
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

^ Pressure is proportional to temperature when volume is held constant.

.In order to restore the substance to its original temperature 0' at constant pressure, it would be necessary to supply a further quantity of heat, H, represented by the area between the two adiabatics from FC down to the absolute zero.^ Black distinguished between the quantity (caloric) and the intensity (temperature) of heat.
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

^ In order to restore the substance to its original temperature 0' at constant pressure, it would be necessary to supply a further quantity of heat, H, represented by the area between the two adiabatics from FC down to the absolute zero.

^ S, Specific heat of gas at constant pressure.

.This quantity of heat is the same as that already found in equation (3), but for the small area BFC, which is negligibly small in the limit compared with H. The whole quantity of heat required to raise the temperature from 0" to 0' at constant pressure along the path EC is H+h, which is equal to S(0' - o"), where S is the specific heat at constant pressure.^ Specific Heat at constant Volume .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ T is the temperature at the surface across which the small quantities of heat flow.
  • "Tracing the Second Law", Feature Article, July 2007 11 January 2010 21:25 UTC www.memagazine.org [Source type: FILTERED WITH BAYES]

.Since h = s (o' - 0"), the difference S - s between the specific heats at constant pressure and volume is evidently H/(o' - o"). Substituting for H its value from (3), and employing the notation of the calculus, we obtain the relation S - s =0 (dp /do) (dv/do),.^ Since the work of compression is equal to q, the heat absorbed by the surroundings, q may be substituted in equation (3) to give: q = RT dV/V (4) From equation (1) the entropy gained by the surroundings during restoration from V2 to V1 is: S = q/T (1) Substituting from equation (4): S = R dV/V Upon integrating (a calculus procedure for summing up the individual values of dV/V) we have: S = Rln(V2/V1) (5) Where ln(V2/V1) is the natural logarithm of the ratio of expanded volume to the initial volume, and S is equal to the entropy increase in the surroundings upon restoration compression from V2 to V1.
  • Second Law of Thermodynamics 10 January 2010 17:12 UTC www.fsteiger.com [Source type: FILTERED WITH BAYES]
  • The Second Law of Thermodynamics, Evolution, and Probability 11 January 2010 21:25 UTC www.talkorigins.org [Source type: Reference]

^ At constant volume for an ideal gas, dU = TdS = C V dT, which defines the specific heat at constant volume, C V .
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ At 373.14 K (99.99°C), the boiling point of water is reached at atmospheric pressure, and further additions of heat begin to boil off some of the water at this constant temperature.
  • Entropy - A Basic Understanding : International site for Spirax Sarco 11 January 2010 21:25 UTC www.spiraxsarco.com [Source type: FILTERED WITH BAYES]

.
.(6) in which the partial differential coefficients have the same meaning as in (4).^ And all the properties of the substance may be expressed in terms of G or J and their partial differential coefficients.

^ Since the two expressions (9) are the partial differential-coefficients of a single function E of the independent variables v and 0, we shall obtain the same result, namely d 2 E/d0dv, if we differentiate the first with respect to v and the second with respect to 0.

^ The values of the partial differential coefficients in terms of n and c are as follows: - Substituting these values in equations already given, we find, from (6) S - s =R(I +nc/V)2 (24) „ (9) dE/dv (o const) =ncp/V .

.Since the amounts of heat supplied at constant pressure from E to F and from E to C are in the limit proportional to the expansions EF and EC which they produce, the ratio S/s is equal to the ratio ECÆF. EF is the change of volume corresponding to a change of pressure BE when no heat is allowed to escape and the path is the adiabatic BF, EC is the change of volume for the same change of pressure BE when the path is the isothermal BC. These changes of volume are directly as the compressibilities, or inversely as the elasticities.^ Specific Heat at constant Volume .
  • Thermodynamics 10 January 2010 17:12 UTC gphysics.net [Source type: Academic]

^ Since the amounts of heat supplied at constant pressure from E to F and from E to C are in the limit proportional to the expansions EF and EC which they produce, the ratio S/s is equal to the ratio ECÆF. EF is the change of volume corresponding to a change of pressure BE when no heat is allowed to escape and the path is the adiabatic BF, EC is the change of volume for the same change of pressure BE when the path is the isothermal BC. These changes of volume are directly as the compressibilities, or inversely as the elasticities.

^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

.If we write K for the adiabatic elasticity, and k for the isothermal elasticity, we obtain S/s = ECÆF = K/k.^ If we write K for the adiabatic elasticity , and k for the isothermal elasticity, we obtain S/s = ECÆF = K/k.

^ K, k, Adiabatic and isothermal elasticities.

... .(7) The value of the specific heat S at constant pressure can always be determined by experiment, and in practice is one of the most important thermodynamical properties of a substance.^ The value of the specific heat S at constant pressure can always be determined by experiment, and in practice is one of the most important thermodynamical properties of a substance.

^ It is generally taken as constant, but its value at moderate pressures is difficult to determine.

^ Specific heat of gas at constant volume.

.The value of the specific heat s at constant volume can also be measured in a few cases, but it is generally necessary to deduce it from that at constant pressure, by means of relation (6).^ The value of the specific heat s at constant volume can also be measured in a few cases, but it is generally necessary to deduce it from that at constant pressure, by means of relation (6).

^ It is generally taken as constant, but its value at moderate pressures is difficult to determine.

^ Specific heat of gas at constant volume.

.It is often impossible to observe the pressure-coefficient dp/de directly, but it may be deduced from the isothermal compressibility by means of the geometrically obvious relation, BE = (BEÆC) XEC. The ratio BEÆC of the diminution of pressure to the increase of volume at constant temperature, or - dp/dv, is readily observed.^ Constant pressure expansion/compression work.
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

^ The coefficient of expansion at constant pressure is equal to the coefficient of increase of pressure at constant volume.

^ Isothermal - Describes a process for which the temperature is constant.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

.The amount of heat absorbed in any small change of state, as from E to G in fig.^ The amount of heat absorbed in any small change of state, as from E to G in fig.

^ To compute the system’s change in energy, take it from its first to its second state, divide each infinitesimal amount of heat by the temperature that’s absorbed by the system, and add all the quantities.
  • Skeptic Friends Network - 2nd Law of Thermodynamics Argument Weak on Both Sides 11 January 2010 21:25 UTC www.skepticfriends.org [Source type: Original source]

^ The equation states the following: The change in entropy of a system is equal to the heat flowing into the system divided by the temperature (in degrees Kelvin).
  • Physics: The Laws of Thermodynamics - CliffsNotes 11 January 2010 21:25 UTC www.cliffsnotes.com [Source type: FILTERED WITH BAYES]

.2, may be found by adding to the heat required for the change of temperature at constant volume, sdo, or at constant pressure, Sdo, the heat absorbed in isothermal expansion as given by relations (4).^ Both the volume and temperature change.
  • Physics: The Laws of Thermodynamics - CliffsNotes 11 January 2010 21:25 UTC www.cliffsnotes.com [Source type: FILTERED WITH BAYES]

^ This added heat changed the temperature of the band.

^ For systems at constant pressure, the absorption of heat results in both a temperature rise and an expansion in volume .
  • New Page 1 10 January 2010 17:12 UTC www.eng.uc.edu [Source type: Academic]

.We thus obtain the expressions dH = sdo +0 (dp I dO) dv = Sd0 - o (dv/do) dp..^ We thus obtain the relation ds/dv(o const) =od 2 p/d0 2 (v const),.

^ The equation to these lines in terms of v and 0 is obtained by integrating dE=sd0+(Odp/de - p)dv = o .

^ Differentiating equation (17) at constant pressure to find dv/do, and observing that dcldO= - nc/O, we find by substitution in (is) the following simple expression for the cooling effect do/dp in terms of c and b, Sdo/dp= (n+I)c - b..

.
.(8) The first is equivalent to measuring the heat along the path EBG, the second along the path ECG. The two differ by the area BEC, which can be neglected if the change is small.^ The first is equivalent to measuring the heat along the path EBG, the second along the path ECG. The two differ by the area BEC, which can be neglected if the change is small.

^ This is the basis of calorimetry, where the work done is equivalent to and is measured as the change in heat of the system.

^ There are two different heat capacities.
  • New Page 1 10 January 2010 17:12 UTC www.eng.uc.edu [Source type: Academic]

.For a finite change it is necessary to represent the path by a series of small steps, which is the graphic equivalent of integration along the path represented by the given relation between v and 0, or p and 0. If we put dH=o in equations (8), we obtain the relations between dv and do, or dp and do, under the condition of no heat-supply, i.e. along the adiabatic, which can be integrated, giving the equations to the adiabatics, provided that the values of the specific heats and expansion-coefficients are known.^ For a finite change it is necessary to represent the path by a series of small steps, which is the graphic equivalent of integration along the path represented by the given relation between v and 0, or p and 0.

^ If we put dH=o in equations (8), we obtain the relations between dv and do, or dp and do, under the condition of no heat-supply, i.e.

^ The TdS equations relate the specific heats to the entropy and to derivatives of the equation of state.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

Missing image
Thermodynamics-3.jpg
6. Intrinsic Energy. - .The change of intrinsic energy E along any path is found by subtracting the work pdv from either of the expressions for dH. Since the change of energy is independent of the path, the finite change between any two given states may be found by integration along any convenient path.^ The change of intrinsic energy E along any path is found by subtracting the work pdv from either of the expressions for dH. Since the change of energy is independent of the path, the finite change between any two given states may be found by integration along any convenient path.

^ The expression for the change of entropy between any two states is found by dividing either of the expressions for dH in (8) by 0 and integrating between the given limits, since dH/B is a perfect differential.

^ For a finite change it is necessary to represent the path by a series of small steps, which is the graphic equivalent of integration along the path represented by the given relation between v and 0, or p and 0.

.It is generally convenient to divide the path into two steps, isothermal and isometric, or isothermal and isopiestic, and to integrate along each separately.^ It is generally convenient to divide the path into two steps, isothermal and isometric, or isothermal and isopiestic, and to integrate along each separately.

^ One could just as easily use a statistical argument - divide a reaction vessel into enough separate compartments, and it is virtually certain that some very unlikely reaction path will occur in one of them.
  • Evolution myths: Evolution violates the second law of thermodynamics - life - 16 April 2008 - New Scientist 11 January 2010 21:25 UTC www.newscientist.com [Source type: FILTERED WITH BAYES]

^ The change of intrinsic energy E along any path is found by subtracting the work pdv from either of the expressions for dH. Since the change of energy is independent of the path, the finite change between any two given states may be found by integration along any convenient path.

.The change of energy at constant volume is simply sdo, the change at constant temperature is (odp/de - p)dv, which may be written dE/de (v const) =s, dE/dv (0 const) =odp/do - p . (9) These must be expressed as functions of v and 0, which is theoretically possible if the values of s, p, and dp/do are known.^ Infinitesimal changes at constant temperatures in these energies are expressed as .

^ Both the volume and temperature change.
  • Physics: The Laws of Thermodynamics - CliffsNotes 11 January 2010 21:25 UTC www.cliffsnotes.com [Source type: FILTERED WITH BAYES]

^ So q is not a state function, w is not a state function but DE and E the internal energy are state functions.
  • Chemistry: The First Law of Thermodynamics | MindBites.com 11 January 2010 21:25 UTC www.mindbites.com [Source type: FILTERED WITH BAYES]

.Since the two expressions (9) are the partial differential-coefficients of a single function E of the independent variables v and 0, we shall obtain the same result, namely d 2 E/d0dv, if we differentiate the first with respect to v and the second with respect to 0. We thus obtain the relation ds/dv(o const) =od 2 p/d0 2 (v const),.^ If u(x,y) is a function of two variables, then it is an exact function and its total derivative is an exact differential if the total differential of u may be written and the second partial derivatives obey the reciprocal relation .
  • Phase Equilibria Glossary 11 January 2010 21:25 UTC www.gps.caltech.edu [Source type: Reference]

^ Since the two expressions (9) are the partial differential-coefficients of a single function E of the independent variables v and 0, we shall obtain the same result, namely d 2 E/d0dv, if we differentiate the first with respect to v and the second with respect to 0.

^ They were given that name because, in the 19th century, they were first discovered in relation to steam engines.
  • LAWS OF NATURE VS. EVOLUTION - 1 11 January 2010 21:25 UTC www.pathlights.com [Source type: Original source]

.. (io) FIG. 2.
Missing image
Thermodynamics-4.jpg
FIG. 3.
which is useful for calculating the variation of the specific heat s with variation of .density at constant temperature.^ In the special case when there are no external forces such as gravity or electrostatic interactions, the density and temperature are constant, with v 0 = 0, and by summing over all 3-D space, Eq.

^ If the density (and kinetic energy) of electrons decreases at constant temperature and pressure, the number of charge electrons decreases, thus decreasing the kinetic energy of the orbital electrons .
  • Westlund Tech Claims Second Law of Thermodynamics is Invalid 11 January 2010 21:25 UTC www.pureenergysystems.com [Source type: FILTERED WITH BAYES]

^ At a constant temperature and pressure, the kinetic energy of electrons is determined by their density.
  • Westlund Tech Claims Second Law of Thermodynamics is Invalid 11 January 2010 21:25 UTC www.pureenergysystems.com [Source type: FILTERED WITH BAYES]

.A similar expression for the variation of the specific heat S at constant pressure is obtained from the second expression in (8), by taking p and 0 as independent variables; but it follows more directly from a consideration of the variation of the function (E+pv).^ Specific heat of gas at constant volume.

^ S, Specific heat of gas at constant pressure.

^ (I I) This expression shows that the rate of variation of the total heat with temperature at constant pressure is equal to the specific heat at constant pressure.

7. Total Heat. - .The
function F= (E+pv), like E itself, has a value depending only on the state of the body.^ The function F= (E+pv), like E itself, has a value depending only on the state of the body.

^ The value and sign of this dc voltage, like the one of the persistent current, depend in a periodical way on a magnetic field with period corresponded to the flux quantum within the loop.
  • New Challenges to the Second Law - Quantum Limits to the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.ipmt-hpm.ac.ru [Source type: Academic]

^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

.It may conveniently be called the Total Heat, by a slight extension of the meaning of a term which has been for a long time in use as applied to vapours (see Vaporization).^ See Terms of Use for details.
  • Thermodynamics/The Second Law of Thermodynamics - Wikiversity 11 January 2010 21:25 UTC en.wikiversity.org [Source type: Academic]

^ It was called the latent heat L, and the term is still used.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ It may conveniently be called the Total Heat, by a slight extension of the meaning of a term which has been for a long time in use as applied to vapours (see Vaporization ).

.Since dE=dH - pdv, we have evidently for the variation of the total heat from the second expression (8), dF=d(E + pv) =dH+vdp=Sde - (Odv/de - v)dp . (I I) This expression shows that the rate of variation of the total heat with temperature at constant pressure is equal to the specific heat at constant pressure.^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ He also showed that the difference of the specific heats at constant pressure and volume, S - s, must be the same for equal volumes of all gases at the same temperature and pressure, being represented by the expression R/TF'(t).

^ Specific heat of gas at constant volume.

.To find the total heat of a substance in any given state defined by the values of p and 0, starting from any convenient zero of temperature, it is sufficient to measure the total heat required to raise the substance to the final temperature under a constant pressure equal to p. For instance, in the boiler of a steam engine the feed water is pumped into the boiler against the final pressure of the steam, and is heated under this constant pressure up to the temperature of the steam.^ For instance, a heat engine has a high-temperature heat reservoir at a single well-defined temperature, T H .

^ Steam engines are a good example of a heat engine.
  • The second law of thermodynamics - Total equilibrium and heat engines. 11 January 2010 21:25 UTC www.flyingturtle.org [Source type: Original source]

^ Find the change in enthalpy for water that is heated from 125 °C to 225 °C at constant pressure of 1 bar.

.The total heat with which we are actually concerned in the working of a steam engine is the total heat as here defined, and not the total heat as defined by Regnault, which, however, differs from (E+pv) only by a quantity which is inappreciable in ordinary practice.^ Steam engines How Steam engines work .

^ The total heat with which we are actually concerned in the working of a steam engine is the total heat as here defined, and not the total heat as defined by Regnault, which, however, differs from ( E+pv ) only by a quantity which is inappreciable in ordinary practice.

^ This allows to define the main difference between work (w) and heat (q).
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.Observing that F is a function of the co-ordinates expressing the state of the substance, we obtain for the variation of S with pressure at constant temperature, dS/dp (0 const) '=' 2 F/dedp =-0d 2 v/d0 2 (p const) (12) If the heat supplied to a substance which is expanding reversibly and doing external work, pdv, is equal to the external work done, the intrinsic energy, E, remains constant.^ When temperature and pressure are held constant, the Gibbs function is a minimum at equilibrium.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ One such variable of state is temperature.
  • Second Law of Thermodynamics - SkepticWiki 11 January 2010 21:25 UTC www.skepticwiki.org [Source type: Original source]

^ Energy required heating up substances .

.The lines of constant energy on the diagram are called Isenergics. The equation to these lines in terms of v and 0 is obtained by integrating dE=sd0+(Odp/de - p)dv = o . (13) If, on the other hand, the heat supplied is equal to - vdp, we see from (I I) that F remains constant.^ Constant pressure lines on the T - s diagram.
  • The Design of Gas Turbine Engines-Thermodynamics and Aerodynamics-2nd Ed: CD ROM & DVD - CD-ROM 11 January 2010 21:25 UTC catalog.asme.org [Source type: Academic]

^ Unfortunately, the constant total heat lines shown in a T - S diagram are curved, which makes it difficult to follow changes in such free and unrestricted expansions as those when steam is allowed to flow through and expand after a control valve.
  • Entropy - A Basic Understanding : International site for Spirax Sarco 11 January 2010 21:25 UTC www.spiraxsarco.com [Source type: FILTERED WITH BAYES]

^ If we combine the first and second laws as expressed in equations 7-1 and 7-2 and replace the mechanical work term W by P V, where P is pressure and V is volume change, we obtain, [NOTE: Volume expansion ( V> 0) corresponds to the system doing work, and therefore losing energy.
  • Thermodynamics of Living Systems 10 January 2010 17:12 UTC www.ldolphin.org [Source type: Academic]

.The equation to the lines of constant total heat is found in terms of p and 0 by putting dF=o and integrating (it).^ The equation to the lines of constant total heat is found in terms of p and 0 by putting dF=o and integrating (it).

^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ When heat is transformed into any other form of energy, or when other forms of energy are transformed into heat, the total amount of energy (heat plus other forms) in the system is constant .
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

8. Ideal Gases

.An ideal gas is a substance possessing very simple thermodynamic properties to which actual gases and vapours appear to approximate indefinitely at low pressures and high temperatures.^ In practice, the temperature is extrapolated to zero pressure, where the gas will be ideal in fact.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ Thermodynamic Temperature Scale - A temperature scale that is independent of the properties of the substances that are used to measure temperature.
  • Thermodynamics Definitions and Terminology - Engineers Edge 10 January 2010 17:12 UTC www.engineersedge.com [Source type: Reference]

^ A gas will always migrate from an area of high pressure to one of low pressure.
  • The Second Law of Thermodynamics :: CESE :: Coalition for Excellence in Science and Math Education 11 January 2010 21:25 UTC www.cesame-nm.org [Source type: Original source]

.It has the characteristic equation pv=Re, and obeys Boyle's law at all temperatures.^ It has the characteristic equation pv=Re, and obeys Boyle's law at all temperatures.

^ If the fluid is a gas also obeying Boyle's law, pv = f (0), then it must be an ideal gas.

^ Thomas Andrew , in a series of experiments with CO 2 through 1869, finds that at low temperatures Boyle's law breaks down, and there are regions on a PV chart where, for a given isotherm, changes in volume produce no change in pressure.
  • Sketching the History of Statistical Mechanics and Thermodynamics 11 January 2010 21:25 UTC omega.math.albany.edu:8008 [Source type: Academic]

.The coefficient of expansion at constant pressure is equal to the coefficient of increase of pressure at constant volume.^ The coefficient of expansion at constant pressure is equal to the coefficient of increase of pressure at constant volume.

^ At constant volume and pressure: .
  • THERMODYNAMICS FOR CHEMICAL ENGINEERS 10 January 2010 17:12 UTC www.assignmenthelp.net [Source type: Academic]

^ R is the molar gas constant , p the pressure, and V the volume of the gas.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

.The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p. The adiabatic elasticity is equal to y p, where -y is the ratio S/s of the specific heats.^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ These results for the difference and the ratio of the specific heats at constant pressure and constant volume are very important and useful.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ Specific heat of gas at constant volume.

.The heat absorbed in isothermal expansion from vo to v at a temperature 0 is equal to the work done by equation (8) (since d0 =o, and 0(dp/d0)dv =pdv), and both are given by the expression RO log e (v/vo).^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ Sdo, the heat absorbed in isothermal expansion as given by relations (4).

^ No work is done and therefore no heat flows in the isothermal free expansion: .
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.The energy E and the total heat F are functions of the temperature only, by equations (9) and (I I), and their variations take the form dE = sdO, d F = Sd0. The specific heats are independent of the pressure or density by equations (to) and (12).^ Heat is a form of energy.

^ At a constant temperature and pressure, the kinetic energy of electrons is determined by their density.
  • Westlund Tech Claims Second Law of Thermodynamics is Invalid 11 January 2010 21:25 UTC www.pureenergysystems.com [Source type: FILTERED WITH BAYES]

^ S, Specific heat of gas at constant pressure.

.If we also assume that they are constant with respect to temperature (which does not necessarily follow from the characteristic equation, but is generally assumed, and appears from Regnault's experiments to be approximately the case for simple gases), the expressions for the change of energy or total heat from 00 to 0 may be written E - Eo = s(0 - 0 0), F - Fo = S(0-00). In thiscase the ratio of the specific heats is constant as well as the difference, and the adiabatic equation takes the simple form, pv v = constant, which is at once obtained by integrating the equation for the adiabatic elasticity, - v(dp/dv) =yp.^ The last partial is just the ratio of dp to dV in this case, when dS = 0.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ Total energy change.
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

.The specific heats may be any function of the temperature consistently with the characteristic equation provided that their difference is constant.^ Specific heats of different types of gases: .
  • THERMODYNAMICS FOR CHEMICAL ENGINEERS 10 January 2010 17:12 UTC www.assignmenthelp.net [Source type: Academic]

^ S, Specific heat of gas at constant pressure.

^ A difference in temperature causes heat to flow.

If we assume that s is a linear function of 0, s= so(I +aO), the adiabatic equation takes the form, s 0 log e OW +aso(0 - Oo) +R loge(v/vo) =o

(14) where (00,v), (e 0, vo) are any two points on the adiabatic. .The corresponding expressions for the change of energy or total heat are obtained by adding the term 2as 0 (02-002) to those already given, thus: E - Eo = so (0-00) + 2 aso (02-002), F - Fo=S0(0-00) + zaso (02-002), where So= so+R. 9. Deviations of Actual Gases from the Ideal State.^ Recall that the changes in Gibbs free energy with pressure and temperature are given by two of Maxwell's relations = r V and = - r S If we recast these as = r V P and = - r S T and integrate, we get r GdP = r G P - r G P ref = r VdP or r G P = r G P ref + r VdP and r GdT = r G T - r G T ref = - r SdT or r G T = r G T ref - r SdT thus r G PT = r G P ref T ref + r VdP - r SdT Solving the Pressure Integral at Constant Temperature .
  • Thermodynamics Notes 10 January 2010 17:12 UTC www.geol.ucsb.edu [Source type: Academic]

^ These energy states at the atomic level change in predictable ways when heating up an aqueous solution, for example.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

^ Heat and work are two methods of adding energy to or subtracting energy from a system.

- .Since
no gas is ideally perfect, it is most important for practical purposes to discuss the deviations of actual gases from the ideal state, and to consider how their properties may be thermodynamically explained and defined.^ Define and explain the First Law of Thermodynamics.

^ Since no gas is ideally perfect, it is most important for practical purposes to discuss the deviations of actual gases from the ideal state, and to consider how their properties may be thermodynamically explained and defined.

^ Define and explain the Second Law of Thermodynamics.

.The most natural method of procedure is to observe the deviations from Boyle's law by measuring the changes of pv at various constant temperatures.^ The most natural method of procedure is to observe the deviations from Boyle's law by measuring the changes of pv at various constant temperatures.

^ The development of life may have only violated one law of science, but that was the one Sir Arthur Eddington called the “supreme” law of Nature, and it has violated that in a most spectacular way.
  • CSI | Does Evolution Have a Thermodynamics Problem? 10 January 2010 17:12 UTC www.csicop.org [Source type: Original source]

^ Trans., 1854, 1862) found that the cooling effect, do, was of the same order of magnitude as the deviations from Boyle's law in each case, and that it was proportional to the difference of pressure, dp, so that d0/dp was nearly constant for each gas over a range of pressure of five or six atmospheres.

.It is found by experiment that the change of pv with pressure at moderate pressures is nearly proportional to the change of p, in other words that the coefficient d(pv)/dp is to a first approximation a function of the temperature only.^ In other words, any entropy change is proportional to the logarithm of the ratio of probabilities.
  • The Second Law of Thermodynamics, Evolution, and Probability 11 January 2010 21:25 UTC www.talkorigins.org [Source type: Reference]

^ It is found by experiment that the change of pv with pressure at moderate pressures is nearly proportional to the change of p, in other words that the coefficient d(pv)/dp is to a first approximation a function of the temperature only.

^ To compute the system’s change in energy, take it from its first to its second state, divide each infinitesimal amount of heat by the temperature that’s absorbed by the system, and add all the quantities.
  • Skeptic Friends Network - 2nd Law of Thermodynamics Argument Weak on Both Sides 11 January 2010 21:25 UTC www.skepticfriends.org [Source type: Original source]

.This coefficient is sometimes called the " angular coefficient," and may be regarded as a measure of the deviations from Boyle's law, 'which may be most simply expressed at moderate pressures by formulating the variation of the angular coefficient with temperature.^ The most natural method of procedure is to observe the deviations from Boyle's law by measuring the changes of pv at various constant temperatures.

^ Using the gas law, we can express both pressure and temperature in terms of and .
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

^ This coefficient is sometimes called the " angular coefficient," and may be regarded as a measure of the deviations from Boyle's law, 'which may be most simply expressed at moderate pressures by formulating the variation of the angular coefficient with temperature.

.But this procedure in itself is not sufficient, because, although it would be highly probable that a gas obeying Boyle's law at all temperatures was practically an ideal gas, it is evident that Boyle's law would be satisfied by any substance having the characteristic equation pv = f (0), where f (0) is any arbitrary function of 0, and that the scale of temperatures given by such a substance would not necessarily coincide with the absolute scale.^ In practice, the temperature is extrapolated to zero pressure, where the gas will be ideal in fact.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ In time, the ideal gas law was formulated.
  • Thermodynamics - encyclopedia article - Citizendium 10 January 2010 17:12 UTC reid.citizendium.org [Source type: Academic]

^ Note that, if it were not an ideal gas, would also depend on p .

.A sufficient test, in addition to Boyle's law, is the condition dE/dv=o at constant temperature.^ A sufficient test, in addition to Boyle's law, is the condition dE/dv=o at constant temperature.

^ From Boyles' Law, we know that the pressure is directly proportional to the temperature, therefore, it was shown that the kinetic energy of the molecules related directly to the temperature of the gas.
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

^ At 373.14 K (99.99°C), the boiling point of water is reached at atmospheric pressure, and further additions of heat begin to boil off some of the water at this constant temperature.
  • Entropy - A Basic Understanding : International site for Spirax Sarco 11 January 2010 21:25 UTC www.spiraxsarco.com [Source type: FILTERED WITH BAYES]

.This gives by equation (9) the condition Odp/d0 =p, which is satisfied by any substance possessing the characteristic equation p/0=f(v), where f(v) is any arbitrary function of v. This test was applied by Joule in the well-known experiment in which he allowed a gas to expand from one vessel to another in a calorimeter without doing external work.^ This test was applied by Joule in the well-known experiment in which he allowed a gas to expand from one vessel to another in a calorimeter without doing external work.

^ Equation (1) gives the sufficient condition that the entropy S is a state function.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

^ Also, the equation applies to non-equilibrium conditions.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

.Under this condition the increase of intrinsic energy would be equal to the heat absorbed, and would be indicated by fall of temperature of the calorimeter.^ As the temperature increases, the probability of the higher energies increases.
  • Thermodynamics 10 January 2010 17:12 UTC www.slideshare.net [Source type: FILTERED WITH BAYES]

^ The kinetic energy contributes to an increase in temperature, the potential energy contributes to an increase in heat capacity.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

^ Under this condition the increase of intrinsic energy would be equal to the heat absorbed, and would be indicated by fall of temperature of the calorimeter.

.Joule failed to observe any change of temperature in his apparatus, and was therefore justified in assuming that the increase of intrinsic energy of a gas in isothermal expansion was very small, and that the absorption of heat observed in a similar experiment in which the gas was allowed to do external work by expanding against the atmospheric pressure was equivalent to the external work done.^ When the gas expands, d x is positive, and the gas does positive work.

^ When heat is transferred to the system, the gas expands, it does work on the surroundings and the temperature and pressure decrease.

^ The change in entropy on expansion is therefore .
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.But owing to the large thermal capacity of his calorimeter, the test, though sufficient for his immediate purpose, was not delicate enough to detect and measure the small deviations which actually exist.^ But owing to the large thermal capacity of his calorimeter, the test, though sufficient for his immediate purpose, was not delicate enough to detect and measure the small deviations which actually exist.

^ (This is an extremely small quantity of heat: roughly one ten-billionth of the heat actually generated by existing electronic circuits.
  • Demons, Engines and the Second Law 11 January 2010 21:25 UTC www.aeiveos.com [Source type: Original source]

^ The thermal properties of water displaying a large heat capacity can explain regulation of temperature in organisms.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

to. .Method of Joule and Thomson.^ Method of Joule and Thomson.

- .William Thomson (Lord Kelvin), who wars the first to realize the importance of the absolute scale in thermodynamics, and the inadequacy of the test afforded by Boyle's law or by experiments on the constancy of the specific heat of gases, devised a more delicate and practical test, which he carried out successfully in conjunction with Joule.^ William Thomson (Baron Kelvin of Largs) : 1852 formulation of the second law of thermodynamics and description of an absolute temperature scale.
  • Selected Classic Papers from the History of Chemistry 10 January 2010 17:12 UTC webserver.lemoyne.edu [Source type: Academic]

^ The first and second laws of thermodynamics emerged simultaneously in the 1850s, primarily out of the works of William Rankine , Rudolf Clausius , and William Thomson (Lord Kelvin).
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

^ In the “diet wars” the first law of thermodynamics has been thrown around a lot.
  • Science-Based Medicine » Calories, Thermodynamics, and Weight 10 January 2010 17:12 UTC www.sciencebasedmedicine.org [Source type: FILTERED WITH BAYES]

.A continuous stream of gas, supplied at a constant pressure and temperature, is forced through a porous plug, from which it issues at a lower pressure through an orifice carefully surrounded with non-conducting material, where its temperature is measured.^ A continuous stream of gas, supplied at a constant pressure and temperature, is forced through a porous plug, from which it issues at a lower pressure through an orifice carefully surrounded with non-conducting material, where its temperature is measured.

^ S, Specific heat of gas at constant pressure.

^ R is the molar gas constant , p the pressure, and V the volume of the gas.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

.If we consider any short length of the stream bounded by two imaginary cross-sections A and B on either side of the plug, unit mass of the fluid in passing A has work, p'v', done on it by the fluid behind and carries its energy, E'+ U', with it into the space AB, where U' is the kinetic energy of flow.^ Class 2D-STREAM-KINETIC-ENERGY .
  • Ontolingua Theory THERMODYNAMICS 10 January 2010 17:12 UTC www-ksl.stanford.edu [Source type: Reference]

^ If we consider any short length of the stream bounded by two imaginary cross-sections A and B on either side of the plug, unit mass of the fluid in passing A has work, p'v', done on it by the fluid behind and carries its energy, E'+ U', with it into the space AB, where U' is the kinetic energy of flow.

^ Heat energy is transformed into work energy.
  • The second law of thermodynamics - Total equilibrium and heat engines. 11 January 2010 21:25 UTC www.flyingturtle.org [Source type: Original source]

.In passing B it does work, p"v", on the fluid in front, and carries its energy, E"+ U", with it out of the space AB. If there is no external loss or gain of heat through the walls of the pipe, and if the flow is steady, so that energy is not accumulating in the space AB, we must evidently have the condition E'+U'+p'v' =E'+ U"+p"v" at any two cross-sections of the stream.^ We can readily see the difficulty in getting polymerization reactions to occur under equilibrium conditions, i.e., in the absence of such an energy flow.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]
  • Thermodynamics and the Origin of Life 11 January 2010 21:25 UTC www.ldolphin.org [Source type: Academic]

^ The coupling of energy flow to the specific work requirements in the formation of DNA and protein is particularly important since the required configurational entropy work of coding is substantial.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ In this case, the S e term represents the negative entropy, or organizing work done on the system as a result of both energy and mass flow through the system.
  • Thermodynamics of Living Systems 10 January 2010 17:12 UTC www.ldolphin.org [Source type: Academic]
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.It is easy to arrange the experiment so that U is small and nearly constant.^ It is easy to arrange the experiment so that U is small and nearly constant.

^ The tires may expand a little, but we assume this effect is small, so the volume is nearly constant.

.In this case the condition of flow is simply that of constant total heat, or in symbols, d(E+pv) =0. We have therefore, by equation, (11), Sd0 = (Odv/d0 - v) d p,.^ For our proof of the efficiency of the Carnot engine, we need only the ratio of Q H to Q L , so we neglect constants of proportionality, and simply subsitutde P ∝ T / V , giving The efficiency of a heat engine is .

^ The equation relating temperature, pressure, and volume of an ideal gas is: PV = RT (2) where: P = pressure V = volume T = absolute temperature R = a constant which depends only on the amount of gas present In the case of a reversible, isothermal compression of an ideal gas we may substitute P from equation (2) into the equation for compression work.
  • Second Law of Thermodynamics 10 January 2010 17:12 UTC www.fsteiger.com [Source type: FILTERED WITH BAYES]

^ The equation to the lines of constant total heat is found in terms of p and 0 by putting dF=o and integrating (it).

... .(15) where d0 is the fall of temperature of the fluid corresponding to a diminution of pressure dp.^ Such a system is only possible at the temperature and pressure corresponding to the Triple point.

^ In the notation of the calculus the relations become - dH/dp (0 const) = odv /do ( p const) (4) dH/dv (0 const) =odp/do ( v const) The negative sign is prefixed to dH/dp because absorption of heat +dH corresponds to diminution of pressure - dp.

^ This means that at a given temperature, water in the gas phase will evaporate or condense until the corresponding equilibrium water vapor pressure is reached.

.If there is no fall of temperature in passing the plug, d0 = o, and we have the condition Odv/d0 =v.^ If there is no fall of temperature in passing the plug, d0 = o, and we have the condition Odv/d0 =v.

^ My previous point, that there is no temperature defined for a nano-scale system, was wrong .
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Careful measurements show that this process occurs without a change in temperature, so there is no energy input or released during the mixing.
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

.The characteristic equation of the fluid must then be of the form v/0=f(p), where f(p) is any arbitrary function of p.^ We now impose the second constraint on the form of the function f: the nature of f must be such that S doubles when the amount of material in the system (N) doubles.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ Since S total = S ( W total ) , S 1 = S ( W 1 ) , and W total = ( W 1 , × , W 1 ) , then our new function S must satisfy the equation S ( ( W 1 , × , W 1 ) ) = S ( W 1 ) + S ( W 1 ) The only function S which will satisfy this equation is the logarithm function, which has the property that ln ( ( x , × , y ) ) = ln x + ln y .
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

^ By multiplying the distribution function with the power of the velocity, e.g., v 0 , v 1 , and v 2 , the continuity equation, Navier-Stokes equations, and conservation of energy respectively in fluid dynamics can be derived directly from Eq.

.If the fluid is a gas also obeying Boyle's law, pv = f (0), then it must be an ideal gas.^ Moles of gas are calculated by the ideal gas law: .
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ If the fluid is a gas also obeying Boyle's law, pv = f (0), then it must be an ideal gas.

^ In time, the ideal gas law was formulated.
  • Thermodynamics - encyclopedia article - Citizendium 10 January 2010 17:12 UTC reid.citizendium.org [Source type: Academic]

.As the result of their experiments on actual gases (air, hydrogen, and C02), Joule and Thomson (Phil.^ As the result of their experiments on actual gases (air, hydrogen , and C02), Joule and Thomson ( Phil.

^ Thomson, W. (1851) On the dynamical theory of heat; with numerical results deduced from Mr. Joule’s equivalent of a thermal unit and M. Regnault’s observations on steam, Math.
  • Second Law of Thermodynamics - a knol by Claes Johnson 10 January 2010 17:12 UTC knol.google.com [Source type: FILTERED WITH BAYES]

^ The values of F'(t) calculated previously by Sir W. Thomson (Lord Kelvin) from Regnault's tables of the properties of steam, assuming the gaseous laws, did not vary exactly as J/T. Joule's experiments on the equivalence of W and H were not sufficiently precise to decide the question.

.Trans., 1854, 1862) found that the cooling effect, do, was of the same order of magnitude as the deviations from Boyle's law in each case, and that it was proportional to the difference of pressure, dp, so that d0/dp was nearly constant for each gas over a range of pressure of five or six atmospheres.^ S, Specific heat of gas at constant pressure.

^ R is the molar gas constant , p the pressure, and V the volume of the gas.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

^ Trans., 1854, 1862) found that the cooling effect, do, was of the same order of magnitude as the deviations from Boyle's law in each case, and that it was proportional to the difference of pressure, dp, so that d0/dp was nearly constant for each gas over a range of pressure of five or six atmospheres.

.By experiments at different temperatures between o° and 00° C., they found that the cooling effect per atmosphere of pressure varied inversely as the square of the absolute temperature for air and CO 2.^ This is the difference between the pressure we want to find and atmospheric pressure at the surface.

^ By experiments at different temperatures between o° and 00° C., they found that the cooling effect per atmosphere of pressure varied inversely as the square of the absolute temperature for air and CO 2 .

^ He remarks that ” the law according to which the motive power of heat varies at different points of the thermometric scale is intimately connected with that of the variations of the specific heats of gases at different temperatures - a law which experiment has not yet made known to us with sufficient exactness."

.Putting d0/dp=A/0 2 in equation (15), and integrating on the assumption that the small variations of S could be neglected over the range of the experiment, they found a solution of the type, v/0 =f(p) - SA /30 3 , in which f(p) is an arbitrary function of p.^ On a small log line, one can find various types of headrigs, ranging from a chipper-canter to a completely integrated machine centre like a four-sided canter..."
  • Martindale's Calculators On-Line Center: Mechanical Engineering: S-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

^ By experiments at different temperatures between o° and 00° C., they found that the cooling effect per atmosphere of pressure varied inversely as the square of the absolute temperature for air and CO 2 .

^ It was decided that this type of experiment could present problems in some classroom settings.

.Assuming that the gas should approximate indefinitely to the ideal state pv = R0 at high temperatures, they put f(p)=Rip, which gives a characteristic equation of the form v= Re/p - SA /30 2 .^ The ideal gas equation of state is .

^ It has the characteristic equation pv=Re, and obeys Boyle's law at all temperatures.

^ The equation of state of one mole of an ideal gas is .
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

. .(16) An equation of a similar form had previously been employed by Rankine (Trans.^ An equation of a similar form had previously been employed by Rankine ( Trans.

Roy. Soc. .Ed., 1854) to represent Regnault's experiments on the deviations of CO 2 from.^ Ed., 1854) to represent Regnault's experiments on the deviations of CO 2 from.

^ The value of the co-aggregation volume, c, at any temperature, assuming equation (17), may be found by observing the deviations from Boyle's law and by experiments on the Joule-Thomson effect.

Boyle's law. .This equation is practically identical for moderate pressures with that devised by Clausius (Phil.^ This equation is practically identical for moderate pressures with that devised by Clausius ( Phil.

.Mag., 1880) to represent the behaviour of CO 2 up to the critical point.^ Mag., 1880) to represent the behaviour of CO 2 up to the critical point.

^ Near the point of crossover from the realm of thermodynamic disorder to the domain of coherence, molecular fluctuations play a critical role in the behaviour of the system.
  • Ralph Dumain: "The Autodidact Project": Shaun Lovejoy: "Christopher Caudwell and the Second Law of Thermodynamics" 11 January 2010 21:25 UTC www.autodidactproject.org [Source type: FILTERED WITH BAYES]

.Experiments by Natanson on CO 2 at 17° C. confirm those of Joule and Thomson, but show a slight increase of the ratio do/dp at higher pressures, which is otherwise rendered probable by the form of the isothermals as determined by Andrews and Amagat.^ Experiments by Natanson on CO 2 at 17° C. confirm those of Joule and Thomson, but show a slight increase of the ratio do/dp at higher pressures, which is otherwise rendered probable by the form of the isothermals as determined by Andrews and Amagat.

^ As the temperature increases, the probability of the higher energies increases.
  • Thermodynamics 10 January 2010 17:12 UTC www.slideshare.net [Source type: FILTERED WITH BAYES]

^ Of greater interest, particularly from a historical point of view, are the original papers of Joule, Thomson and Rankine, some of which have been reprinted in a collected form.

.More recent experiments by J. H. Grindley (Proc.^ More recent experiments by J. H. Grindley ( Proc.

Roy. .Soc., 1900, 66, p.^ Soc., 1900, 66, p.

79) and Callendar (Proc. Roy. Soc., 1900) on steam confirm this type of equation, but give much larger values of the cooling effect than for C02, and a more rapid rate of variation with temperature.
.I I. Modified Joule-Thomson Equation.^ I I. Modified Joule-Thomson Equation.

^ The value of the co-aggregation volume, c, at any temperature, assuming equation (17), may be found by observing the deviations from Boyle's law and by experiments on the Joule-Thomson effect.

^ In the modified Joule-Thomson equation (17), both c and n have simple theoretical interpretations, and it is possible to express the thermodynamical properties of the substance in terms of them by means of reasonably simple formulae.

- .G.
A. Hirn (Theorie Mec.^ G. A. Hirn ( Theorie Mec.

de la Chaleur, ii.
p. .211, Paris, 1869) proposed an equation of the form (p+po)(v - b) =RO, in which the effect of the size of the molecules is represented by subtracting a quantity b, the " covolume," from the volume occupied by the gas, and the effect of the mutual attractions of the molecules is represented by adding a quantity po, the internal pressure, to the external pressure, p.^ Any gas is specified by its temperature , the volume it occupies and its pressure .
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

^ R is the molar gas constant , p the pressure, and V the volume of the gas.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

^ Gas in a container is at a pressure of 1.5 atm and a volume of 4 m 3 .

.This type of equation, was more fully worked out by van der Waals, who identified the internal pressure, po, with the capillary pressure of Laplace, and assumed that it varied directly as the square of the density, and could be written a/v 2 . This assumption represents qualitatively the theoretical isothermal of James Thomson (see Vaporization) and the phenomena of the critical state (see Condensation Of Gases); but the numerical results to which it leads differ so widely from experiment that it is necessary to suppose the constant, a, to be a function of the temperature.^ Suppose the pressure in the two gases is identical.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

^ (See reference 2 for what we mean by “function of state”.
  • Thermodynamics and Differential Forms 10 January 2010 17:12 UTC www.av8n.com [Source type: Academic]

^ The above equation could have been written .
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

.Many complicated expressions have been suggested by subsequent writers in the attempt to represent the continuity of the gaseous and liquid states in a single formula, but these are of a highly empirical nature, and beyond the scope of the present inquiry.^ Specific natural processes > > to which can be attributed the entropy decreases necessarily > > associated with the generation of these things have similarly > > not been empirically and unequivocally demonstrated.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ (One can’t help but wonder whether this paragraph is meant as an attempt to go beyond the myth of spontaneous generation to suggest the notion of spontaneous resurrection!
  • - Thermodynamics vs. Evolutionism - 11 January 2010 21:25 UTC www.trueorigin.org [Source type: Original source]

^ For example: water which is in a gaseous state (steam) can release energy in change from gas to liquid while not changing temperature, although the pressure does change.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.The simplest assumption which suffices to express the small deviations of gases and vapours from the ideal state at moderate pressures is that the coefficient a in the expression for the capillary pressure varies inversely as some power of the absolute temperature.^ For some substances, the magnetic susceptibility varies inversely as the temperature.
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

^ The simplest assumption which suffices to express the small deviations of gases and vapours from the ideal state at moderate pressures is that the coefficient a in the expression for the capillary pressure varies inversely as some power of the absolute temperature.

^ From the ideal gas law, the ratio of the pressures is the same as the ratio of the absolute temperatures, .

.Neglecting small terms of the second order, the equation may then be written in the form v - b=RO/p - co(Oo/O)=V - c,..^ In working to a first approximation, the small term nc/V may be omitted in the expression for s.

^ We can re-order the terms in the above equation to calculate the critical size of the nucleus r c r c = -2 / ( V G + ) If, at the critical radius, n G = G*, the activation energy for nucleation is G* = 16 3 / 3( V G + ) 2 Growth .
  • Thermodynamics Notes 10 January 2010 17:12 UTC www.geol.ucsb.edu [Source type: Academic]

^ If we combine the first and second laws as expressed in equations 7-1 and 7-2 and replace the mechanical work term W by P V, where P is pressure and V is volume change, we obtain, .
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.(17) in which c is a small quantity (expressing the defect from the ideal volume V =Re/p due to co-aggregation of the molecules) which varies inversely as the nth power of 0, but is independent of p to a first approximation at moderate pressures.^ V =Re/p due to co- aggregation of the molecules) which varies inversely as the nth power of 0, but is independent of p to a first approximation at moderate pressures.

^ If we combine the first and second laws as expressed in equations 7-1 and 7-2 and replace the mechanical work term W by P V, where P is pressure and V is volume change, we obtain, [NOTE: Volume expansion ( V> 0) corresponds to the system doing work, and therefore losing energy.
  • Thermodynamics of Living Systems 10 January 2010 17:12 UTC www.ldolphin.org [Source type: Academic]

^ The simplest assumption which suffices to express the small deviations of gases and vapours from the ideal state at moderate pressures is that the coefficient a in the expression for the capillary pressure varies inversely as some power of the absolute temperature.

.The constant co is the value of c at some standard temperature oo.^ The constant co is the value of c at some standard temperature oo.

^ An example of a heat bath is a swimming pool maintained at some constant temperature.
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

^ Denoting by So, so, these constant limiting values at p=o, we may obtain the values at any pressure by integrating the expressions (27) and (28) from co to v and from o to p respectively.

.The value of the index, n, appears to be different for different types of molecule.^ States of monolayers in p -A isotherms The type of a monolayer formed (with characteristic p -A isotherms) by different lipids will depend on the intermolecular forces between the molecules at the surface.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

^ A bacterium is more complex, more differentiated, possessing a cell wall and different types of molecules and a metabolism.
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

^ I prefer to avoid this dispersal of molecules in our thought experiment, because I want the thermodynamic case to appear as different as possible from the previous experiment with the gas molecules in a container that disperse in a room.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

.For CO 2 at ordinary temperatures n =2, as in the JouleThomson equation.^ For CO 2 at ordinary temperatures n =2, as in the JouleThomson equation.

^ The value of the co-aggregation volume, c, at any temperature, assuming equation (17), may be found by observing the deviations from Boyle's law and by experiments on the Joule-Thomson effect.

.For steam between Ioo° and 150° C. it approaches the value 3.5. It is probably less than 2 for air and the more perfect gases.^ It is precariously perched between the molten core of the earth, with more energy than the systems could tolerate, and space, where temperatures approach the absolute zero your refer to.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The universe moves from its less probable current arrangement (low entropy) toward its most probable arrangement in which the energy of the universe will be more uniformly distributed.
  • Thermodynamics of Living Systems 10 January 2010 17:12 UTC www.ldolphin.org [Source type: Academic]

^ In other words, an isolated system always goes from a less probable to a more probable configuration.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

.The introduction of the covolume,
b, into the equation is required in order to enable it to represent the behaviour of hydrogen and other gases at high temperatures and pressures according to the experiments of Amagat.^ However, according to the formula S = Q/T, less heat need be expelled into the low temperature reservoir than is extracted from the high temperature reservoir for equal and opposite changes in entropy.
  • thermodynamics Facts, information, pictures | Encyclopedia.com articles about thermodynamics 10 January 2010 17:12 UTC www.encyclopedia.com [Source type: Academic]

^ In this equation, Q is a quotient of partial pressures of the gases in the reaction mixture.
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

^ And an example of this is a rock will always fall if you let go of it a great height Or high pressure will always leak into a low pressure.
  • Can someone please explain the The Second Law of Thermodynamics to me, with examples? | Ask MetaFilter 11 January 2010 21:25 UTC ask.metafilter.com [Source type: Original source]

.It is generally taken as constant, but its value at moderate pressures is difficult to determine.^ It is generally taken as constant, but its value at moderate pressures is difficult to determine.

^ The value of the specific heat s at constant volume can also be measured in a few cases, but it is generally necessary to deduce it from that at constant pressure, by means of relation (6).

^ The value of the specific heat S at constant pressure can always be determined by experiment, and in practice is one of the most important thermodynamical properties of a substance.

.According to van der Waals, assuming spherical molecules, it should be four times; according to O. E. Meyer, on slightly different assumptions, it should be 41/2 times, the actual volume of the molecules.^ According to van der Waals, assuming spherical molecules, it should be four times; according to O. E. Meyer, on slightly different assumptions, it should be 41/2 times, the actual volume of the molecules.

^ By taking into accounts the attraction between molecules and their finite size (total volume of the gas is represented by the red square in Figure 06), a more realistic equation for the real gases known as van der Waals equation was derived way back in 1873: .

^ Van der Waals bonds) exhibit sharp, large peaks in the heat capacity curve.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.It appears to be a quantity of the same order as the volume of the liquid, or as the limiting volume of the gas at very high pressures.^ Gas in a container is at a pressure of 1.5 atm and a volume of 4 m 3 .

^ It appears to be a quantity of the same order as the volume of the liquid, or as the limiting volume of the gas at very high pressures.

^ R is the molar gas constant , p the pressure, and V the volume of the gas.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

.The value of the co-aggregation volume,
c, at any temperature, assuming equation (17), may be found by observing the deviations from Boyle's law and by experiments on the Joule-Thomson effect.^ During the 19th century, the second law was synthesized, essentially, by studying the dynamics of the Carnot heat engine in coordination with James Joule's Mechanical equivalent of heat experiments.
  • Second law of thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 11 January 2010 21:25 UTC www.chemie.de [Source type: FILTERED WITH BAYES]

^ From Boyles' Law, we know that the pressure is directly proportional to the temperature, therefore, it was shown that the kinetic energy of the molecules related directly to the temperature of the gas.
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

^ We are interested in the variation of S with pressure, and we remember from Boyle's law that, for a fixed temperature, volume is inversely related to pressure.
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

.The value of the angular coefficient
d(pv)/dp is evidently (b - c), which expresses the defect of the actual volume v from the ideal volume Re/p.^ The value of the angular coefficient d(pv)/dp is evidently (b - c), which expresses the defect of the actual volume v from the ideal volume Re/p.

^ From the ideal gas law PV=nRT , the volume of such a sample can be used as an indicator of temperature; in this manner it defines temperature.
  • Thermodynamics - encyclopedia article - Citizendium 10 January 2010 17:12 UTC reid.citizendium.org [Source type: Academic]
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

^ These must be expressed as functions of v and 0, which is theoretically possible if the values of s, p, and dp/do are known.

.Differentiating equation (17) at constant pressure to find dv/do, and observing that dcldO= - nc/O, we find by substitution in (is) the following simple expression for the cooling effect do/dp in terms of c and b, Sdo/dp= (n+I)c - b..^ The difference of the specific heats by equation (6) is constant and equal to R. The isothermal elasticity - v(dp/dv) is equal to the pressure p.

^ During this constant-volume reheating, we have PV = nkT , so the amount of pressure regained is a direct indication of how much the gas cooled down when it lost an amount of energy Δ E .

^ It would do away with the well-developed mathematical relationships of physical chemistry, including the effect of temperature and pressure on equilibrium constants and phase changes.
  • Second Law of Thermodynamics 10 January 2010 17:12 UTC www.fsteiger.com [Source type: FILTERED WITH BAYES]

. .(18) Experiments at two temperatures suffice to determine both c and n if we assume that b is equal to the volume of the liquid.^ Experiments at two temperatures suffice to determine both c and n if we assume that b is equal to the volume of the liquid.

^ If experiments show that the two partial derivatives are equal, the second law is confirmed.
  • BIASED THERMAL MOTION AND THE SECOND LAW OF THERMODYNAMICS 11 January 2010 21:25 UTC wbabin.net [Source type: FILTERED WITH BAYES]

^ Moreover entropy cannot be measured directly, there is no such thing as an entropy meter, whereas state parameters like volume and temperature are easily determined.
  • Entropy (thermodynamics) - encyclopedia article - Citizendium 10 January 2010 17:12 UTC locke.citizendium.org [Source type: Academic]

.But it is better to apply the Boyle's law test in addition, provided that errors due to, surface condensation can be avoided.^ But it is better to apply the Boyle's law test in addition, provided that errors due to, surface condensation can be avoided.

^ If lifting is due to an additional pressure generated within the bulk, as assumed by Panofsky and Phillips, then water will leak through the hole and the second law will be violated.
  • BIASED THERMAL MOTION AND THE SECOND LAW OF THERMODYNAMICS 11 January 2010 21:25 UTC wbabin.net [Source type: FILTERED WITH BAYES]

^ The Second Law is simple in principle, but applying it to real systems can be difficult due to the challenge of determining probabilities at the microscopic level.
  • Evolution & Entropy - Second Law of Thermodynamics 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

.The advantage of this type of equation is that
c is a function of the temperature only.^ The advantage of this type of equation is that c is a function of the temperature only.

^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

^ This equation gives us an opportunity to define a temperature scale, by choosing the function f.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.Other favourite types' of equation for approximate work are (I) p=RO/v±f(v), which makes p a linear function of 0 at constant volume, as in van der Waal's equation; (2) v=RO/p+f(p), which makes
v a linear function of 0 at constant pressure.^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

^ The standard transformed enthalpy of reaction r H' o can be calculated with the van't Hoff equation from apparent equilibrium constants which have been determined as a function of temperature.
  • Thermodynamics of Enzyme-Catalyzed Reactions 10 January 2010 17:12 UTC xpdb.nist.gov [Source type: Academic]

^ Van der Waals bonds) exhibit sharp, large peaks in the heat capacity curve.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.These have often been employed as empirical formulae (e.g.^ These have often been employed as empirical formulae (e.g.

.Zeuner's formula for steam), but they cannot be made to represent with sufficient approximation the deviations from the ideal state at moderate pressures and generally lead to erroneous results.^ Zeuner's formula for steam), but they cannot be made to represent with sufficient approximation the deviations from the ideal state at moderate pressures and generally lead to erroneous results.

^ V =Re/p due to co- aggregation of the molecules) which varies inversely as the nth power of 0, but is independent of p to a first approximation at moderate pressures.

^ Many practical examples approximate the conditions of uniform state and uniform flow sufficiently well for engineering calculations.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

In the modified Joule-Thomson equation (17), both
c and n have simple theoretical interpretations, and it is possible to express the thermodynamical properties of the substance in terms of them by means of reasonably simple formulae.
dv/dO (p const) = (R/p) (I +nc/V)..
(19)
d 2 v/d0 2 „ _ - n(n+ I)c/e 2. .
20)
dp/do (v const) = (R/V) (I +nc/V).
21)
d 2 p/d0 e „ =Rnc(I - n+2ne/V)/0V 2.
(22)
d(pv)/dp(o const) = b - c
. (23)
.12. Application of the Modified Equation.^ Application of the Modified Equation.

- .We
may take equation (17) as a practical example of the thermodynamical principles already given.^ We may take equation (17) as a practical example of the thermodynamical principles already given.

^ Consequently, we are talking here non-equlibrium thermodynamics/statistical mechanics, for which there is no minimum principle, just Liouville's equation (classically).
  • 'Evolution as Described by the Second Law of Thermodynamics' by PhysoOrg - RichardDawkins.net 11 January 2010 21:25 UTC richarddawkins.net [Source type: FILTERED WITH BAYES]

^ Thermodynamic laws are concerned with the relationship between thermal energy properties of a system and are given as mathematical equations or equations of state (literally meaning an equation describing the relationship between properties of a system).
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.The values of the partial differential coefficients in terms of n and c are as follows: - Substituting these values in equations already given, we find, from (6) S - s =R(I +nc/V)2 (24) „ (9) dE/dv (o const) =ncp/V . (25) „ (11) dF/dp „ = n+i)c - b . (26) „ (10) ds/dv (I - n+2nc/V)Rnc/V2 (27) „ (12) dS/dp „ =n(n+I)c/e.^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

^ This gives TdS = C V dT + T(∂p/∂T) V dV. Now dS is given in terms of experimentally measurable quantities only.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ The last partial is just the ratio of dp to dV in this case, when dS = 0.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

..)
.In order to deduce the complete variation of the specific heats from these equations, it is necessary to make some assumption with regard to the variation of the specific heats with temperature.^ Under these assumptions the equation is as follows: .
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ In order to deduce the complete variation of the specific heats from these equations, it is necessary to make some assumption with regard to the variation of the specific heats with temperature.

^ He remarks that ” the law according to which the motive power of heat varies at different points of the thermometric scale is intimately connected with that of the variations of the specific heats of gases at different temperatures - a law which experiment has not yet made known to us with sufficient exactness."

.The assumption usually made is that the total kinetic energy of the molecules, including possible energy of rotation or vibration if the molecules consist of more than one atom, is proportional to the energy of translation in the case of an ideal gas.^ (A more complex molecule could rotate and vibrate as well.

^ The total kinetic energy is an extensive quantity.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Internal Energy - The internal energy ( U ) of a system is the total energy due to the motion of molecules, plus the rotation, and vibration of atoms within molecules.

.In the case of imperfect gases, all the available experimental evidence shows that the specific volume tends towards its ideal value, V =Re/p, in the limit, when the pressure is indefinitely reduced and the molecules are widely separated so as to eliminate the effects of their mutual actions.^ At constant volume for an ideal gas, dU = TdS = C V dT, which defines the specific heat at constant volume, C V .
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ In this case, all gases behave like an "Ideal Gas" and have a very simple relation between their pressure, volume, and temperature: pV= (constant)T. This temperature is called the thermodynamic temperature and is now accepted as the fundamental measure of temperature.
  • About Temperature 10 January 2010 17:12 UTC eo.ucar.edu [Source type: Academic]

^ A crucial observation is that although solids and liquids are nearly incompressible, gases can be compressed, as when we increase the amount of air in a car's tire while hardly increasing its volume at all.

.We may therefore reasonably assume that the limiting values of the specific heats at zero pressure do not vary with the temperature, provided that the molecule is stable and there is no dissociation.^ So, there is no reason for amusement.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ The entropy is therefore zero at zero temperature.

^ In practice, the temperature is extrapolated to zero pressure, where the gas will be ideal in fact.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

.Denoting by So, so, these constant limiting values at p=o, we may obtain the values at any pressure by integrating the expressions (27) and (28) from co to v and from o to p respectively.^ Although pressure is defined mechanically, a pressure-measuring device, called a barometer may also be constructed from a sample of an ideal gas held at a constant temperature.
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

^ These results for the difference and the ratio of the specific heats at constant pressure and constant volume are very important and useful.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ When necessary, results have been adjusted to units of mol dm -3 to obtain the numerical value(s) of K c given in these tables.
  • Thermodynamics of Enzyme-Catalyzed Reactions 10 January 2010 17:12 UTC xpdb.nist.gov [Source type: Academic]

.We thus obtain S=So±n(n+I)pc/O. s= so+ (n - I - nc/V)ncp/o. In working to a first approximation, the small term nc/V may be omitted in the expression for s. The expression for the change of intrinsic energy E between any given limits poOo to po is readily found by substituting these values of the specific heats in equations (II) or (13), and integrating between the given limits.^ Heat and work may be exchanged with the surroundings and thereby induce changes in energy and volume.
  • Evolution violates the Second Law of Thermodynamics - Page 2 - Science Forums 11 January 2010 21:25 UTC hypography.com [Source type: FILTERED WITH BAYES]

^ The change of intrinsic energy E along any path is found by subtracting the work pdv from either of the expressions for dH. Since the change of energy is independent of the path, the finite change between any two given states may be found by integration along any convenient path.

^ In working to a first approximation, the small term nc/V may be omitted in the expression for s.

.We thus obtain E - g o= s 0 (B-o)) - n(pc - poco) (31) We have similarly for the total heat F = E + pv, F - Fo=So(O - oo) - (n+1)(cp - copo)+b(p - p.^ The corresponding expressions for the change of energy or total heat are obtained by adding the term 2as 0 (02-002) to those already given, thus: E - Eo = so (0-00) + 2 aso (02-002), F - Fo=S0(0-00) + zaso ( 02-002 ), where So= so+R. 9.

^ The total heat with which we are actually concerned in the working of a steam engine is the total heat as here defined, and not the total heat as defined by Regnault, which, however, differs from ( E+pv ) only by a quantity which is inappreciable in ordinary practice.

^ F= E+pv, Total heat.

).
.The energy is less than that of an ideal gas by the term npc.^ The energy is less than that of an ideal gas by the term npc.

^ The reaction cycles down a very long potential energy gradient, controlled by kinetics rather than thermodynamics in the short term.
  • Evolution myths: Evolution violates the second law of thermodynamics - life - 16 April 2008 - New Scientist 11 January 2010 21:25 UTC www.newscientist.com [Source type: FILTERED WITH BAYES]

^ There is a specific physical energy requirement to lift oil (and gas under less pressure) out of the ground.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

.If we imagine that the defect of volume c is due to the formation of molecular aggregates consisting of two or more single molecules, and if the kinetic energy of translation of any one of these aggregates is equal to that of one of the single molecules, it is clear that some energy must be lost in co-aggregating, but that the proportion lost will be different for different types of molecules and also for different types of co-aggregation.^ If we imagine that the defect of volume c is due to the formation of molecular aggregates consisting of two or more single molecules, and if the kinetic energy of translation of any one of these aggregates is equal to that of one of the single molecules, it is clear that some energy must be lost in co-aggregating, but that the proportion lost will be different for different types of molecules and also for different types of co-aggregation.

^ The energy must be directed in some way.
  • Jeff's Lunchbreak: Creation Museum/Creationist Rule of Thumb with the 2nd Law of Thermodynamics 11 January 2010 21:25 UTC www.jefflewis.net [Source type: Original source]

^ By symmetry, it must therefore equal 2/3 of the total kinetic energy, so .

.If two monatomic molecules, having energy of translation only, equivalent to 3 degrees of freedom, combined to form a diatomic molecule with 5 degrees of freedom, the energy lost would.^ I.e., what matters is kinetic energy per degree of freedom, not kinetic energy per molecule?
  • Less Wrong: The Second Law of Thermodynamics, and Engines of Cognition 11 January 2010 21:25 UTC lesswrong.com [Source type: Original source]

^ You still have two degrees of freedom, but now you have six variables and four equations.

^ Molecules could briefly extract energy from their surroundings, combining in ways that would otherwise be impossible in practice.
  • Law of Thermodynamics Faces Repeal - WSJ.com 11 January 2010 21:25 UTC online.wsj.com [Source type: General]

be pc/2 for co-aggregation, .c, per unit mass.^ E, Intrinsic energy per unit mass.

^ An intensive property can be derived from every extensive property by considering the extensive property per unit mass or mole of the substance.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ Density - Density ( ) is defined as mass per unit volume.

.In this case n =1/2. If two diatomic molecules, having each 5 degrees of freedom, combine to form a molecule with 6 degrees of freedom, we should have n = 2, or the energy lost would be 2pc per unit mass.^ I.e., what matters is kinetic energy per degree of freedom, not kinetic energy per molecule?
  • Less Wrong: The Second Law of Thermodynamics, and Engines of Cognition 11 January 2010 21:25 UTC lesswrong.com [Source type: Original source]

^ If two monatomic molecules, having energy of translation only, equivalent to 3 degrees of freedom, combined to form a diatomic molecule with 5 degrees of freedom, the energy lost would.

^ If two diatomic molecules, having each 5 degrees of freedom, combine to form a molecule with 6 degrees of freedom, we should have n = 2, or the energy lost would be 2pc per unit mass.

.If the molecules and molecular aggregates were more complicated, and the number of degrees of freedom of the aggregates were limited to 6, or were the same as for single molecules, we should have n-= so/R. The loss of energy could not be greater than this on the simple kinetic theory, unless there were some evolution of latent heat of co-aggregation, due to the work done by the mutual attractions of the co-aggregating molecules.^ But if there were no more to the mechanism of molecular evolution than this, we should still be at a loss to understand how more and more complex molecules cam to establish themselves.
  • Second Law of Thermodynamics - SkepticWiki 11 January 2010 21:25 UTC www.skepticwiki.org [Source type: Original source]

^ Evolution is more than just a theory, it's a fact.
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

^ I.e., what matters is kinetic energy per degree of freedom, not kinetic energy per molecule?
  • Less Wrong: The Second Law of Thermodynamics, and Engines of Cognition 11 January 2010 21:25 UTC lesswrong.com [Source type: Original source]

.It is not necessary to suppose that the co-aggregated molecules are permanently associated.^ It is not necessary to suppose that the co-aggregated molecules are permanently associated.

^ V =Re/p due to co- aggregation of the molecules) which varies inversely as the nth power of 0, but is independent of p to a first approximation at moderate pressures.

.They are continually changing partners, the ratio c/V representing approximately the ratio of the time during which any one molecule is paired to the time during which it is free.^ They are continually changing partners, the ratio c/V representing approximately the ratio of the time during which any one molecule is paired to the time during which it is free.

^ Given this tautology, computer scientists are free to choose one of a number of abstract quantities that are conserved over time to use as the "energy" of a system.
  • ACM Sigplan Notices 29, 4 (Apr 1994), 58-63. 10 January 2010 17:12 UTC www.pipeline.com [Source type: FILTERED WITH BAYES]

^ During dynamic equilibrium , counter-balancing "reactions that are reversible" occur at the microscopic level of molecules, even though (by the definition of equilibrium) no change is occurring at the macroscopic level.
  • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

.At higher densities it is probable that more complex aggregates would be formed, so that as the effect of the collisions became more important c would cease to be a function of the temperature only; experiment, indeed, shows this to be the case.^ At higher densities it is probable that more complex aggregates would be formed, so that as the effect of the collisions became more important c would cease to be a function of the temperature only; experiment, indeed, shows this to be the case.

^ Away from equilibrium, highly ordered stable complex systems can emerge, develop and grow at the expense of more disorder at higher levels in the system's hierarchy.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

^ At high temperatures, entropy becomes more important.
  • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

13. Entropy. - .It follows from the definition of the absolute scale of temperature, as given in relations (2), that in passing at constant temperature 0 from one adiabatic 4' (Fig.^ Your "definition" of temperature has the following roots.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ In the notes, I adopted the following definition of temperature T: .
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Here is the definition of the absolute temperature T .
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.I) to any other adiabatic 0", the quotient H/o of the heat absorbed by the temperature at which it is absorbed is the same for the same two adiabatics whatever the temperature of the isothermal path.^ I) to any other adiabatic 0", the quotient H/o of the heat absorbed by the temperature at which it is absorbed is the same for the same two adiabatics whatever the temperature of the isothermal path.

^ A cycle such as ABCD enclosed by parts of two isothermals, BC, AD, and two adiabatics, AB, CD, is the simplest form of cycle for theoretical purposes, since all the heat absorbed, H', is taken in during the process represented by one isothermal at the temperature o', and all the heat rejected, H", is given out during the process represented by the other at the temperature 0".

^ Thus, we write dS > then > and recalling that C P = then > and S = dT In other words, the vibrational entropy can be found by integrating the heat capacity divided by temperature.
  • Thermodynamics Notes 10 January 2010 17:12 UTC www.geol.ucsb.edu [Source type: Academic]

.This quotient is called the change of entropy, and may be denoted by (4,"-0').^ The heat absorbed in this change is called the latent heat of change of state, and may be represented by the symbol L'.

^ This quotient is called the change of entropy, and may be denoted by (4,"-0').

^ If two systems are brought into thermal contact, the entropy of one may decrease, and the entropy of the other increase, but the net entropy change will be zero or positive.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

.In passing along an adiabatic there is no change of entropy, since no heat is absorbed.^ In passing along an adiabatic there is no change of entropy, since no heat is absorbed.

^ Even if the expansion is adiabatic, in the sense that it takes place inside a non-conducting enclosure and no heat is supplied from external sources, it will not be isentropic, since the heat supplied by internal friction must be included in reckoning the change of entropy.

^ Since only changes in entropy are defined, it was thought that there was an additive constant which would always be arbitrary.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

.The adiabatics are lines of constant entropy, and are also called Isentropics. In virtue of relations (2), the change of entropy of a substance between any two states depends only on the initial and final states, and may be reckoned along any reversible path, not necessarily isothermal, by dividing each small increment of heat, dH, by the temperature, 0, at which it is acquired, and taking the sum or integral of the quotients, dH/o, so obtained.^ Recall entropy depends only on the the state of the gas.
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

^ An isentropic process (reversible adiabatic process) occurs at a constant entropy.
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

^ So the initial state of the gas is , and the final state of the gas is .
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

.(29) (30) The expression for the change of entropy between any two states is found by dividing either of the expressions for dH in (8) by 0 and integrating between the given limits, since dH/B is a perfect differential.^ The increase in entropy is given by the integral of δ Q / T for any reversible process between these two states.
  • Second Law of Thermodynamics - SkepticWiki 11 January 2010 21:25 UTC www.skepticwiki.org [Source type: Original source]

^ The change of intrinsic energy E along any path is found by subtracting the work pdv from either of the expressions for dH. Since the change of energy is independent of the path, the finite change between any two given states may be found by integration along any convenient path.

^ The expression for the change of entropy between any two states is found by dividing either of the expressions for dH in (8) by 0 and integrating between the given limits, since dH/B is a perfect differential.

.In the case of a solid or a liquid, the latent heat of isothermal expansion may often be neglected, and if the specific heat, s, be also taken as constant, we have simply 0-00 =s log e0/00. If the substance at the temperature 0 undergoes a change of state, absorbing latent heat, L, we have merely to add the term Lie to the above expression.^ This added heat changed the temperature of the band.

^ When we heat ice, it changes from a solid phase to a liquid phase to a gaseous phase.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ For solids and liquids, we see that the difference in the specific heats is small, and γ is about 1.0.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

In the case of an ideal gas, dp/d9 at constant volume =R/v, and dvld6 at constant pressure =R/p; thus we obtain the expressions for the change of entropy 0-4)0 from the state poeovo to the state pev, log e e/eo+R logev/vo =S log e 9/00-R (32) In the case of an imperfect gas or vapour, the above expressions are frequently employed, but a more accurate result may be obtained by employing equation (17) with the value of the specific heat, S, from (29), which gives the expression 4-¢o = Sologe0/00 - R logep/po-n(cp/B-copo/Bo)
.(33) The state of a substance may be defined by means of the temperature and entropy as co-ordinates, instead of employing the pressure and volume as in the indicator diagram.^ The state of a substance may be defined by means of the temperature and entropy as co-ordinates, instead of employing the pressure and volume as in the indicator diagram.

^ Typically, a system the entropy of which we wish to know has been defined in terms of common macroscopic thermodynamic properties that we have at our disposal and with which the reader may already be familiar such as volume, pressure, temperature, and internal energy for which we have not given formal definitions.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ Realize that when we write dG = VdP - SdT we are implicitly writing dG = dP - dT which means that = V and = -S These relations indicate that the change in Gibbs free energy with respect to pressure is the molar volume V and the change in Gibbs free energy with respect to temperature is minus the entropy S. Gibbs Free Energy of Formation .
  • Thermodynamics Notes 10 January 2010 17:12 UTC www.geol.ucsb.edu [Source type: Academic]

.This method of representation is applicable to certain kinds of problems, and has been developed by Macfarlane Gray and other writers in its application to the steam engine.^ This method of representation is applicable to certain kinds of problems, and has been developed by Macfarlane Gray and other writers in its application to the steam engine.

^ From here, a semblance of a thermo-science began to develop with the construction of the first successful atmospheric steam engines in England by Thomas Savery in 1697 and Thomas Newcomen in 1712.
  • Thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 10 January 2010 17:12 UTC www.chemie.de [Source type: Academic]

^ Readers will find clear and concise presentations, sound developments of the fundamentals, and state-of-the-art engineering applications.
  • Powell's Books - Fundamentals of Engineering Thermodynamics (6TH 08 Edition) by Michael J. Moran 11 January 2010 21:25 UTC www.powells.com [Source type: Academic]

.(See Steam Engine.^ (See Steam Engine .

^ This next toy is an example of the simplest steam engine you will ever see.
  • Chapter 5: Thermodynamics -- Building simple heat engines 10 January 2010 17:12 UTC sci-toys.com [Source type: FILTERED WITH BAYES]

) .Areas on the temperature-entropy or 0, 4, diagram represent quantities of heat in the same way as areas on the indicator diagram represent quantities of work.^ Areas on the temperature-entropy or 0, 4, diagram represent quantities of heat in the same way as areas on the indicator diagram represent quantities of work.

^ In the early 19th century, it slowly became evident that heat was not a conserved quantity, as it should have been if it were material, but that work and heat were interconvertible.
  • Thermodynamics 11 January 2010 21:25 UTC mysite.du.edu [Source type: Academic]

^ The area of the cycle, viz., that enclosed by the path Bcda , represents the balance of external work done by the substance in one cycle, and is positive if the cycle is described clockwise 0' O as indicated by the arrows.

.The 0, 4) diagram is useful in the study of heat waste and condensation, but from other points of view the utility of the conception of entropy as a " factor of heat " is limited by the fact that it does not correspond to any directly measurable physical property, but is merely a mathematical function arising from the form of the definition of absolute temperature.^ The "reversibility" restriction on the heat in the definition of entropy is necessary if entropy is to be a state function.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ What does work in a cycle correspond to on a P-V diagram?
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

^ For any system, entropy is a physically measurable quantity.
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

.Changes of entropy must be calculated in terms of quantities of heat, and must be interpreted in a similar manner.^ Changes of entropy must be calculated in terms of quantities of heat, and must be interpreted in a similar manner.

^ The second term is the change in the entropy of the system.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

^ Even if the expansion is adiabatic, in the sense that it takes place inside a non-conducting enclosure and no heat is supplied from external sources, it will not be isentropic, since the heat supplied by internal friction must be included in reckoning the change of entropy.

The majority of thermodynamical problems may be treated without any reference to entropy, but it affords a convenient method of expression in abstract thermodynamics, especially in the consideration of irreversible processes and in reference to the conditions of equilibrium of heterogeneous systems.
14. Irreversible Processes. - .In order that a process may be strictly reversible, it is necessary that the state of the working substance should be one of equilibrium at uniform pressure and temperature throughout.^ D S univ > 0 for a spontaneous process D S univ = 0 for a reversible process (a process in equilibrium).
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ In order that a process may be strictly reversible, it is necessary that the state of the working substance should be one of equilibrium at uniform pressure and temperature throughout.

^ A reversible process is one in which the system and surroundings are in equilibrium throughout the process .
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.If heat passes " of itself " from a higher to a lower temperature by conduction, convection or radiation, the transfer cannot be reversed without an expenditure of work.^ If heat passes " of itself " from a higher to a lower temperature by conduction, convection or radiation, the transfer cannot be reversed without an expenditure of work.

^ Heat cannot spontaneously flow from a material at lower temperature to a material at higher temperature.
  • Second law of thermodynamics: Encyclopedia of chemistry, analytics & pharmaceutics with 64,557 entries. 11 January 2010 21:25 UTC www.chemie.de [Source type: FILTERED WITH BAYES]

^ Actually, it can be transferred by three methods: conduction, convection, and radiation.

.If mechanical work or kinetic energy is directly converted into heat by friction, reversal of the motion does not restore the energy so converted.^ In essence, it is a device which converts heat energy into mechanical work, like moving pistons, levers and so on.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

^ If mechanical work or kinetic energy is directly converted into heat by friction, reversal of the motion does not restore the energy so converted.

^ This combined kinetic energy then gets converted into gravitational potential energy.

.In all such cases there is necessarily, by Carnot's principle, a loss of efficiency or available energy, accompanied by an increase of entropy, which serves as a convenient measure or criterion of the loss.^ There is never a net increase in potential energy, nor is there a net decrease in entropy.
  • Evolution violates the Second Law of Thermodynamics - Science Forums 10 January 2010 17:12 UTC hypography.com [Source type: FILTERED WITH BAYES]

^ In all such cases there is necessarily, by Carnot's principle, a loss of efficiency or available energy, accompanied by an increase of entropy, which serves as a convenient measure or criterion of the loss.

^ Entropy is a measure of order and energy in a system.
  • The Second Law of Thermodynamics 10 January 2010 17:12 UTC www.irfi.org [Source type: FILTERED WITH BAYES]

.A common illustration of an irreversible process is the expansion of a gas into a vacuum or against a pressure less than its own.^ A common illustration of an irreversible process is the expansion of a gas into a vacuum or against a pressure less than its own.

^ To illustrate how to calculate the change in entropy in an irreversible process, consider the irreversible free expansion of an ideal gas from an initial volume into a vacuum such that its final volume is .
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

^ Similarly, the heat transferred to the system is a maximum in the reversible process, and is less than this maximum for any irreversible process.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.In this case the work of expansion, pdv, is expended in the first instance in producing kinetic energy of motion of parts of the gas.^ In this case the work of expansion, pdv, is expended in the first instance in producing kinetic energy of motion of parts of the gas.

^ In this case, the S e term represents the negative entropy, or organizing work done on the system as a result of both energy and mass flow through the system.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

^ Thus, the efficiency in terms of the work produced relative to the high-temperature energy absorbed is ( TH - TL )/ TH = ( deltaT )/ TH .
  • ACM Sigplan Notices 29, 4 (Apr 1994), 58-63. 10 January 2010 17:12 UTC www.pipeline.com [Source type: FILTERED WITH BAYES]

.If this could be co-ordinated and utilized without dissipation, the gas might conceivably be restored to its initial state; but in practice violent local differences of pressure and temperature are produced, the kinetic energy is rapidly converted into heat by viscous eddy friction, and residual differences of temperature are equalized by diffusion throughout the mass.^ If mechanical work or kinetic energy is directly converted into heat by friction, reversal of the motion does not restore the energy so converted.

^ So the initial state of the gas is , and the final state of the gas is .
  • Entropy 11 January 2010 21:25 UTC srikant.org [Source type: FILTERED WITH BAYES]

^ Then the heat energy is converted into mechanical energy that can be used to do work.
  • The Second Law of Thermodynamics 10 January 2010 17:12 UTC www.irfi.org [Source type: FILTERED WITH BAYES]

.Even if the expansion is adiabatic, in the sense that it takes place inside a non-conducting enclosure and no heat is supplied from external sources, it will not be isentropic, since the heat supplied by internal friction must be included in reckoning the change of entropy.^ The entropy change for the universe in this expansion is .
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ Even if the expansion is adiabatic, in the sense that it takes place inside a non-conducting enclosure and no heat is supplied from external sources, it will not be isentropic, since the heat supplied by internal friction must be included in reckoning the change of entropy.

^ The change in entropy on expansion is therefore .
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.Assuming that no heat is supplied from external sources and no external work is done, the intrinsic energy remains constant by the first law.^ Specifically, the first law addresses the interconvertability of work and heat as forms of energy.

^ The first law is the law of conservation of energy.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Internal energy = heat + work .

.The final state of the substance, when equilibrium has been restored, may be deduced from this condition, if the energy can be expressed in terms of the co-ordinates.^ The final condition is thermal equilibrium.
  • Overcoming Bias : Scandalous Heat 10 January 2010 17:12 UTC www.overcomingbias.com [Source type: Original source]

^ The final state of the substance, when equilibrium has been restored, may be deduced from this condition, if the energy can be expressed in terms of the co-ordinates.

^ We can readily see the difficulty in getting polymerization reactions to occur under equilibrium conditions, i.e., in the absence of such an energy flow.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]
  • Thermodynamics and the Origin of Life 11 January 2010 21:25 UTC www.ldolphin.org [Source type: Academic]

.But the line of constant energy on - the diagram does not represent the path of the transformation, unless it be supposed to be effected in a series of infinitesimal steps between each of which the substance is restored to an equilibrium state.^ The lines of constant energy on the diagram are called Isenergics.

^ But the line of constant energy on - the diagram does not represent the path of the transformation, unless it be supposed to be effected in a series of infinitesimal steps between each of which the substance is restored to an equilibrium state.

^ In the limiting case of a long fine tube, the bore of which varies in such a manner that U is constant, the state of the substance along a line of flow may be represented by the line of constant total heat, d(E+pv) = o; but in the case of a porous plug or small throttling aperture , the steps of the process cannot be followed, though the final state is the same.

.An irreversible process which permits a more complete experimental investigation is the steady flow of a fluid in a tube already referred to in section to.^ An irreversible process which permits a more complete experimental investigation is the steady flow of a fluid in a tube already referred to in section to.

^ The numerous quantitative relations derived from this law have been subjected to more and more accurate experimental investigation without the detection of the slightest inaccuracy."—* G.N. Lewis and *M. Randall, Thermodynamics (1961), p.

^ Prigogine has developed a more general formulation of the laws of thermodynamics which includes nonlinear, irreversible processes such as autocatalytic activity.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.If the tube is a perfect non-conductor, and if there are no eddies or frictional dissipation, the state of the substance at any point of the tube as to E, p, and v, is represented by the adiabatic or isentropic path, dE= -pdv. As the section of the tube varies, the change of kinetic energy of flow, dU, is represented by The flow in this case is reversible, and the state of the fluid is the same at points where the section of the tube is the same.^ There is initially no variation.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ If the tube is a perfect non-conductor, and if there are no eddies or frictional dissipation, the state of the substance at any point of the tube as to E, p, and v, is represented by the adiabatic or isentropic path, dE= -pdv.

^ U, Kinetic energy of flow of fluid.

.In practice, however, there is always some frictional dissipation, accompanied by an increase of entropy and by a fall of pressure.^ But the entropy of a system does not always increase.
  • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

^ But in this reaction, and in those below, there is always an entropy increase for the universe.
  • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

^ In practice, however, there is always some frictional dissipation, accompanied by an increase of entropy and by a fall of pressure.

.In the limiting case of a long fine tube, the bore of which varies in such a manner that U is constant, the state of the substance along a line of flow may be represented by the line of constant total heat, d(E+pv) = o; but in the case of a porous plug or small throttling aperture, the steps of the process cannot be followed, though the final state is the same.^ For such a process the change in any state function is 0.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ If we make they contact with a large system, this may destroy the states of the real systems and make them have the same temperature of the large system itself.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ In this case, the S e term represents the negative entropy, or organizing work done on the system as a result of both energy and mass flow through the system.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.In any small reversible change in which the substance absorbs heat, dH, from external sources, the increase of entropy, d0, must be equal to dH/9. If the change is not reversible, but the final state is the same, the change of entropy, do, is the same, but it is no longer equal to dII/B. By Carnot's principle, in all irreversible processes, dH/0 must be algebraically less than do, otherwise it would be possible to devise a cycle more efficient than a reversible cycle.^ One of the processes by which entropy is increased is life.
  • 'Evolution as Described by the Second Law of Thermodynamics' by PhysoOrg - RichardDawkins.net 11 January 2010 21:25 UTC richarddawkins.net [Source type: FILTERED WITH BAYES]

^ Reversible and irreversible process .
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

^ Similarly, the heat transferred to the system is a maximum in the reversible process, and is less than this maximum for any irreversible process.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.This affords a useful criterion (see Energetics) between transformations which are impossible and those which are possible but irreversible.^ This affords a useful criterion (see Energetics ) between transformations which are impossible and those which are possible but irreversible.

^ Second, it is impossible entirely to convert heat into work—something is always lost in energetic transformation.
  • IoHT :: 110+ Variations of the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.humanthermodynamics.com [Source type: Academic]

^ We can also see now that the efficiency of heat engines will increase if we make the temperature difference between the heat source and heat sink as large as possible.
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

.In the special case of a substance isolated from external heat supply, dH=o, the change of entropy is zero in a reversible process, but must be positive if the process is not reversible.^ In any spontaneous irreversible change, if the system is heat-isolated, there must be an increase of entropy.

^ In real processes, the change in total entropy is always positive.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ In any small reversible change in which the substance absorbs heat, dH, from external sources, the increase of entropy, d0, must be equal to dH/9.

.The entropy cannot diminish.^ The entropy cannot diminish.

.Any change involving decrease of entropy is impossible.^ Any change involving decrease of entropy is impossible.

^ For the first type of entropy change, a useful principle (but not the only principle) is to think about constraint change because when there is more constraint and thus less freedom of motion , entropy decreases.
  • Second Law: Entropy, Complexity, and Evolution 11 January 2010 21:25 UTC www.asa3.org [Source type: FILTERED WITH BAYES]

^ The heat involved in this process cannot be used in equation 11-4 to calculate the entropy change of the expansion.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.The entropy tends to a maximum, and the state is one of stable equilibrium when the value of the entropy is the maximum value consistent with the conditions of the problem.^ The entropy tends to a maximum, and the state is one of stable equilibrium when the value of the entropy is the maximum value consistent with the conditions of the problem.

^ Equilibrium is reached when entropy reaches its maximum value, and this means that the system is in its most likely state.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

^ The entropy of the world tends towards a maximum.
  • IoHT :: 110+ Variations of the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.humanthermodynamics.com [Source type: Academic]

15. Heterogeneous Equilibrium. - .In a system, as distinguished from a homogeneous substance, consisting of two or more states or phases, a similar condition of equilibrium applies.^ In a system, as distinguished from a homogeneous substance, consisting of two or more states or phases, a similar condition of equilibrium applies.

^ Also, the equation applies to non-equilibrium conditions.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

.In any spontaneous irreversible change, if the system is heat-isolated, there must be an increase of entropy.^ Entropy for an isolated system can never spontaneously decrease.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

^ We have seen that the entropy of an isolated system increases.
  • Approaching the world’s environmental problems through the Second Law (Entropy Law) of Thermodynamics - Encyclopedia of Earth 11 January 2010 21:25 UTC www.eoearth.org [Source type: FILTERED WITH BAYES]

^ In any spontaneous irreversible change, if the system is heat-isolated, there must be an increase of entropy.

.The total entropy of the system is found by multiplying the entropy per unit mass of the substance in each state by the mass existing in that state, and adding the products so obtained.^ Starting with unit mass of the substance in the first state (e.g.

^ The total entropy of the system is found by multiplying the entropy per unit mass of the substance in each state by the mass existing in that state, and adding the products so obtained.

^ E, Intrinsic energy per unit mass.

.The simplest case to consider is that of equilibrium between solid and liquid, or liquid and vapour.^ This is the point where we have equilibrium between liquid and vapor.
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

^ The simplest case to consider is that of equilibrium between solid and liquid, or liquid and vapour.

^ But let's not bother with that...more importantly it is the case that entropy of the water which forms the snowflafe is reduced with every phase change...when it goes from gas to liquid, and when it goes from liquid to solid.
  • Does Evolutionary Theory Violate the Laws of Thermodynamics? - Debate Nation 11 January 2010 21:25 UTC www.debatenation.com [Source type: General]

.The more general case is discussed in the article Energetics, and in the original memoirs of Willard Gibbs and others.^ The more general case is discussed in the article Energetics , and in the original memoirs of Willard Gibbs and others.

^ First, consider the configurational case, and Brian Greene’s explanation for why molecules (or other material things in general) disperse in space.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

^ In other words, general advice will usually not be considered legal advice absent more specific facts.
  • Patent Law Blog (Patently-O): CAFC Rejects Patent on Invention to Overcome the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.patentlyo.com [Source type: FILTERED WITH BAYES]

.Since the condition of heat-isolation is impracticable, the condition of maximum entropy cannot, as a rule, be directly applied, and it is necessary to find a more convenient method of expression.^ Since the condition of heat-isolation is impracticable, the condition of maximum entropy cannot, as a rule, be directly applied, and it is necessary to find a more convenient method of expression.

^ It is not necessary to suppose that c varies inversely as the nth power of the temperature, and that b is constant, as assumed in deducing the expressions for cp, E, and F. Although the value of G in any case cannot be found without that of 0, and although the consideration of the properties of the thermodynamic potential cannot in any case lead to results which are not directly deducible from the two fundamental laws, it affords a convenient method of formal expression in abstract thermodynamics for the condition of equilibrium between different phases, or the criterion of the possibility of a transformation.

^ Although we cannot prove it here, the entropy increase of a substance due to heat q at temperature T is given by Δ S = .
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

.If dW is the external work done, dH the heat absorbed from external sources, and dE the increase of intrinsic energy, we have in all cases by the first law, dH-dE=dW. Since Od4 cannot be less than dH, the difference (61d4-dE) cannot be less than dW. This inequality holds in all cases, but cannot in general be applied to an irreversible change, because Od4 is not a perfect differential, and cannot be evaluated without a knowledge of the path or process of transformation.^ Heat cannot be completely transformed into work.
  • ECONOMY AND THERMODYNAMICS 10 January 2010 17:12 UTC www.ecen.com [Source type: FILTERED WITH BAYES]

^ Similarly, the heat transferred to the system is a maximum in the reversible process, and is less than this maximum for any irreversible process.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ Laws are expected to apply generally.
  • Jeff's Lunchbreak: Creation Museum/Creationist Rule of Thumb with the 2nd Law of Thermodynamics 11 January 2010 21:25 UTC www.jefflewis.net [Source type: Original source]

.In the special case, however, in which the transformation is conducted in an isothermal enclosure, a common condition easily realized in practice, the temperature at the end of the transformation is reduced to its initial value throughout the substance.^ In the special case, however, in which the transformation is conducted in an isothermal enclosure, a common condition easily realized in practice, the temperature at the end of the transformation is reduced to its initial value throughout the substance.

^ If J', J" represent the values of the function for unit mass of the substance of specific volumes v' and v" in the two states at temperature 0 and pressure and if a mass m is in the state v', and 1-m in the.

^ Under certain conditions, however, heat conduction may occur by a heat-convection current---the coordinated movement of many gas molecules.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.The value of Od4 is then the same as d(64), which is a perfect differential, so that the condition may be written d(46-E) =dW. The condition in this form can be readily applied provided that the external work dW can be measured.^ The value of Od4 is then the same as d(64 ), which is a perfect differential, so that the condition may be written d(46-E) =dW. The condition in this form can be readily applied provided that the external work dW can be measured.

^ If dW is the external work done, dH the heat absorbed from external sources, and dE the increase of intrinsic energy, we have in all cases by the first law, dH-dE=dW. Since Od4 cannot be less than dH, the difference ( 61d4-dE ) cannot be less than dW. This inequality holds in all cases, but cannot in general be applied to an irreversible change, because Od4 is not a perfect differential, and cannot be evaluated without a knowledge of the path or process of transformation.

^ This test was applied by Joule in the well-known experiment in which he allowed a gas to expand from one vessel to another in a calorimeter without doing external work.

There are two. special cases of importance: - .(a) If the volume is constant, or dW=o, the value of the function (00-E) cannot diminish, or (E--94,) cannot increase, if the temperature is kept constant.^ The condition of stable equilibrium of a system at constant temperature and volume is that the total J should be a minimum.

^ The value of the specific heat s at constant volume can also be measured in a few cases, but it is generally necessary to deduce it from that at constant pressure, by means of relation (6).

^ Although we cannot prove it here, the entropy increase of a substance due to heat q at temperature T is given by Δ S = .
  • Equilibrium and the Second Law of Thermodynamics 11 January 2010 21:25 UTC cnx.org [Source type: Academic]

.This function may be represented, for each state or phase of the system considered, by an area on the indicator diagram similar to that representing the intrinsic energy, E. The product 94, may be represented at any point such as D in Fig.^ Stable " describes a system or phase in its lowest energy state.
  • Thermodynamics Notes 10 January 2010 17:12 UTC www.geol.ucsb.edu [Source type: Academic]

^ The product pv for any state such as D in fig.

^ Metastable " describes a system or phase in any other energy state.
  • Thermodynamics Notes 10 January 2010 17:12 UTC www.geol.ucsb.edu [Source type: Academic]

.I by the whole area B"DZ'VO under the isothermal 9"D and the adiabatic DZ', bounded by the axes of pressure and volume.^ I by the whole area B"DZ'VO under the isothermal 9"D and the adiabatic DZ', bounded by the axes of pressure and volume.

^ Topics: Surroundings, boundary, closed system, control volume, property, state, process, thermodynamic cycle, extensive property, intensive property, phase, pure substance, equilibrium, specific volume, pressure, temperature, adiabatic process, isothermal process, temperature scales.
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

^ Since dH = CpdT, the area under the curve is the integral of the differential equation and D H = Cp D T (constant pressure).
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.The intrinsic energy, E, is similarly represented by the area DZ'Vd under the adiabatic to the right of the isometric Dd.^ The intrinsic energy, E, is similarly represented by the area DZ'Vd under the adiabatic to the right of the isometric Dd.

^ If the substance in any state such as B were allowed to expand adiabatically ( dH = o ) down to the absolute zero, at which point it contains no heat and exerts no pressure, the whole of its available heat energy might theoretically be recovered in the form of external work, represented on the diagram by the whole area BAZcb under the adiabatic through the state-point B, bounded by the isometric Bb and the zero isopiestic bV. The change of the intrinsic energy in passing from one state to another, as from B to C is represented by the addition of the heat-area H= Bczz ', and the subtraction of the work-area W = BCcb.

^ The difference 90-E is represented by the area 9"DdO to the left of the isometric Dd under the isothermal B"D. The increment of this area (or the decrement of the negative area E--04 ) at constant temperature represents the external work obtainable from the substance in isothermal expansion, in the same way that the decrement of the intrinsic energy represents the work done in adiabatic expansion.

.The difference 90-E is represented by the area 9"DdO to the left of the isometric Dd under the isothermal B"D. The increment of this area (or the decrement of the negative area E--04) at constant temperature represents the external work obtainable from the substance in isothermal expansion, in the same way that the decrement of the intrinsic energy represents the work done in adiabatic expansion.^ Areas on the temperature-entropy or 0, 4, diagram represent quantities of heat in the same way as areas on the indicator diagram represent quantities of work.

^ These functions do not, however, represent energy existing in the substance, like the intrinsic energy; but the increment of 90 represents heat supplied to, and the decrement of ( E-04 ) represents work obtainable from, the substance when the temperature is kept constant.

^ Constant pressure expansion/compression work.
  • Thermodynamics 10 January 2010 17:12 UTC www.mae.wvu.edu [Source type: Academic]

.The function J = E-94,, has been called the " free energy " of the substance by Helmholtz, and 90 the " bound energy."^ Helmholtz himself suggested that this be divided up (Bailyn 1994) between free energy, which today is more specifically renamed helmholtz energy, and bound energy.
  • Second law Analysis of Gas Turbines...Ben Wiens...innovation consultant...innovating through synergy...value innovation, simple, combined, heat, exchange, recuperated, fuel, cell, solid, oxide, engine, energy, thermodynamics, formulas, efficiency, combustion, conversion, enthalpy, entropy, exergy, availability, cogeneration, recuperation, chemical, looping, westinghouse, rolls, royce, solar, saturn, siemens, ge, steam, temperature, carnot, computer 11 January 2010 21:25 UTC www.benwiens.com [Source type: Academic]

^ Chemists have established rankings of the free energy content of substances so that the amount of energy available can be determined by calculating the differences in the reference values of the materials that react and the materials that are produced.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Here G o is the standard free energy of the substance at the standard condition of 1.0 bar; G is the free energy at arbitrary pressure P; and the other terms are familiar.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.These functions do not, however, represent energy existing in the substance, like the intrinsic energy; but the increment of 90 represents heat supplied to, and the decrement of (E-04) represents work obtainable from, the substance when the temperature is kept constant.^ The boiler contains some substance which is kept at a high temperature by supplying it with energy obtained by converting other (chemical) forms of energy into heat energy - either by burning wood, or fossil fuels and so on.
  • Second Law of Thermodynamics 11 January 2010 21:25 UTC srikant.org [Source type: Original source]

^ Thus, the efficiency in terms of the work produced relative to the high-temperature energy absorbed is ( TH - TL )/ TH = ( deltaT )/ TH .
  • ACM Sigplan Notices 29, 4 (Apr 1994), 58-63. 10 January 2010 17:12 UTC www.pipeline.com [Source type: FILTERED WITH BAYES]

^ Phase transitions like the melting of ice are special kinds of work and indicate the cooperative change in potential energy of a system.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.The condition of stable equilibrium of a system at constant temperature and volume is that the total J should be a minimum.^ The condition of stable equilibrium of a system at constant temperature and volume is that the total J should be a minimum.

^ The condition of stable equilibrium is that G should be a minimum, for which reason it has been called the " thermodynamic potential at constant pressure."

^ Such systems, treated typically using microcanonical ensembles, are fully described by physical quantities such as the total (and conserved) energy, the volume, etc., with no specification of the temperature.
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

.This function is also called the " thermodynamic potential at constant volume " from the analogy with the condition of minimum potential energy as the criterion of stable equilibrium in statics.^ The condition of stable equilibrium of a system at constant temperature and volume is that the total J should be a minimum.

^ The condition of stable equilibrium is that G should be a minimum, for which reason it has been called the " thermodynamic potential at constant pressure."

^ This function is also called the " thermodynamic potential at constant volume " from the analogy with the condition of minimum potential energy as the criterion of stable equilibrium in statics .

.As an example, we may apply this condition to the case of change of state.^ As an example, we may apply this condition to the case of change of state.

^ As the section of the tube varies, the change of kinetic energy of flow, dU, is represented by The flow in this case is reversible, and the state of the fluid is the same at points where the section of the tube is the same.

^ These energy states at the atomic level change in predictable ways when heating up an aqueous solution, for example.
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

.If J', J" represent the values of the function for unit mass of the substance of specific volumes v' and v" in the two states at temperature 0 and pressure and if a mass m is in the state v', and 1-m in the.^ The volume of 1 kg of neon gas as a function of temperature (at standard pressure).

^ It is obviously a function of two states, namely state A and state B .
  • Thermodynamics and Differential Forms 10 January 2010 17:12 UTC www.av8n.com [Source type: Academic]

^ Starting with unit mass of the substance in the first state (e.g.

state .v", the value of J for unit mass of the mixture is mJ' + (1m) This must be a minimum in the state of equilibrium at constant temperature.^ J for unit mass of the mixture is mJ' + (1m ) This must be a minimum in the state of equilibrium at constant temperature.

^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

^ The entropy tends to a maximum, and the state is one of stable equilibrium when the value of the entropy is the maximum value consistent with the conditions of the problem.

.Since the volume is constant, we have the condition mv'--l-(I-m)v"=constant.^ This function is also called the " thermodynamic potential at constant volume " from the analogy with the condition of minimum potential energy as the criterion of stable equilibrium in statics .

^ The condition of stable equilibrium of a system at constant temperature and volume is that the total J should be a minimum.

^ Since such splits and merges violate micro-reversibility, the volume must therefore remain constant.
  • ACM Sigplan Notices 29, 4 (Apr 1994), 58-63. 10 January 2010 17:12 UTC www.pipeline.com [Source type: FILTERED WITH BAYES]

.Since dJ=-4d9-pdv, we have also the relations dJ'/dv' = - p = dJ"/dv", at constant temperature.^ The most instructive example of the application of relations (I) and (2) is afforded by the change of state of a substance at constant temperature and pressure.

^ Heat is being sucked in from the hot reservoir, and since the working gas is always in thermal equilibrium with the hot reservoir, its temperature is constant.

^ Since the thermal energy of an ideal gas depends only on its temperature, there is no change in the thermal energy of the gas during this constant-temperature process.

.Putting dJ /dm =o at constant volume, we obtain as the condition of equilibrium of the two states J' + p'v' = J" -}- p "v". This may be interpreted as the equation of the border curve giving the relation between p and 0, but is more easily obtained by considering the equilibrium at constant pressure instead of constant volume.^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

^ This may be interpreted as the equation of the border curve giving the relation between p and 0, but is more easily obtained by considering the equilibrium at constant pressure instead of constant volume.

^ Also, the equation applies to non-equilibrium conditions.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

.(b) The second case, which is of greater practical utility, is that in which the external pressure, p, is kept constant.^ The second case, which is of greater practical utility, is that in which the external pressure, p, is kept constant.

^ The value of the specific heat s at constant volume can also be measured in a few cases, but it is generally necessary to deduce it from that at constant pressure, by means of relation (6).

^ The value of the specific heat S at constant pressure can always be determined by experiment, and in practice is one of the most important thermodynamical properties of a substance.

.In this case dW=pdv=d(pv), a perfect differential, so that the external work done is known from the initial and final states.^ B is the initial state A is the final state.
  • Thermodynamics and Differential Forms 10 January 2010 17:12 UTC www.av8n.com [Source type: Academic]

^ Since the initial and final states are the same by both paths, D E rev = D E irrev (E is a state function).
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ Figure 9-5 shows the initial and final states of an adiabatic expansion.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

.In any possible transformation d(D4 - E) cannot be less than d(pv), or the function (E - D4)+pv) =G cannot increase.^ Of note here is that creationist do NOT state that increasing order is impossible; such statements are straw-man arguments in order to make it less reasonable than it really is.
  • Evolution Defying Second Law of Thermodynamics [Archive] - TeenSpot.com - Teen Message Boards 11 January 2010 21:25 UTC www.teenspot.com [Source type: Original source]

^ Which is not to say I don't expect to see a fair bit of hardship from dramatically increased energy prices and possible shortages, but I don't see why in the long run it cannot be for the better.
  • The Oil Drum | Why We "Waste" Energy: The Second Law of Thermodynamics Explains--UPDATED 8/7 11 January 2010 21:25 UTC www.theoildrum.com [Source type: FILTERED WITH BAYES]

^ We have seen that for reversible processes, the increase in entropy is always less than for irreversible processes.
  • Approaching the world’s environmental problems through the Second Law (Entropy Law) of Thermodynamics - Encyclopedia of Earth 11 January 2010 21:25 UTC www.eoearth.org [Source type: FILTERED WITH BAYES]

.The condition of stable equilibrium is that G should be a minimum, for which reason it has been called the " thermodynamic potential at constant pressure."^ The condition of stable equilibrium of a system at constant temperature and volume is that the total J should be a minimum.

^ This function is also called the " thermodynamic potential at constant volume " from the analogy with the condition of minimum potential energy as the criterion of stable equilibrium in statics .

^ The condition of stable equilibrium is that G should be a minimum, for which reason it has been called the " thermodynamic potential at constant pressure."

.The product pv for any state such as D in fig.^ The product pv for any state such as D in fig.

^ This function may be represented, for each state or phase of the system considered, by an area on the indicator diagram similar to that representing the intrinsic energy, E. The product 94, may be represented at any point such as D in Fig.

r is represented by the rectangle .MDdO, bounded by the isopiestic and the isometric through D. The function G is represented by the negative area D"DM under the isothermal, bounded by the isopiestic DM and the axis of pressure.^ MDdO, bounded by the isopiestic and the isometric through D. The function G is represented by the negative area D"DM under the isothermal, bounded by the isopiestic DM and the axis of pressure.

^ If the substance in any state such as B were allowed to expand adiabatically ( dH = o ) down to the absolute zero, at which point it contains no heat and exerts no pressure, the whole of its available heat energy might theoretically be recovered in the form of external work, represented on the diagram by the whole area BAZcb under the adiabatic through the state-point B, bounded by the isometric Bb and the zero isopiestic bV. The change of the intrinsic energy in passing from one state to another, as from B to C is represented by the addition of the heat-area H= Bczz ', and the subtraction of the work-area W = BCcb.

^ In this case, the S e term represents the negative entropy, or organizing work done on the system as a result of both energy and mass flow through the system.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.The increment of 00 is always greater than that of the total heat F=E+pv, except in the special case of an equilibrium change at constant temperature and pressure, in which case both are equal to the heat absorbed in the change, and the function G remains constant.^ S, Specific heat of gas at constant pressure.

^ In this case the condition of flow is simply that of constant total heat, or in symbols, d(E+pv) =0.

^ (I I) This expression shows that the rate of variation of the total heat with temperature at constant pressure is equal to the specific heat at constant pressure.

.This is geometrically obvious from the form of the area representing the function on the indicator diagram, and also follows directly from the first law.^ This is our first constraint on the form of the function, f.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ This is geometrically obvious from the form of the area representing the function on the indicator diagram, and also follows directly from the first law.

^ The area of the cycle, viz., that enclosed by the path Bcda , represents the balance of external work done by the substance in one cycle, and is positive if the cycle is described clockwise 0' O as indicated by the arrows.

.The simplest application of the thermodynamic potential is to questions of change of state.^ The simplest application of the thermodynamic potential is to questions of change of state.

^ And the question about the application of thermodynamics to the Universe as a whole is more than a bit irrelevant to the human condition on Earth.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ The most instructive example of the application of relations (I) and (2) is afforded by the change of state of a substance at constant temperature and pressure.

.If 0', E', v'; and 4)", E", v", refer to unit mass of the substance in the first and second states respectively in equilibrium at a temperature 0 and pressure p, the heat absorbed, L, per unit mass in a change from the first to the second state is, by definition of the entropy, equal to 0(4)"-4)'), and this by the first law is equal to the change of intrinsic energy, E" - E', plus the external work done, p(v" - v'), i.e. to the change of total heat, F" - F. If G' and G" are the values of the function G for the two states in equilibrium at the same pressure and temperature, we must have G' =G". Assuming the function G to be expressed in terms of p and 0, this condition represents the relation between p and 0 corresponding to equilibrium between the two states, which is the solution of the relation (v" - v')dp/dO=L/D, (5). The direct integration of this equation requires that L and v" - v' should be known as functions of p and 0, and cannot generally be performed.^ This test was applied by Joule in the well-known experiment in which he allowed a gas to expand from one vessel to another in a calorimeter without doing external work.

^ Another statement of the 2nd law is that, for any isolated system, the entropy remains the same during any reversible process and increases during any irreversible process.
  • The Second Law of Thermodynamics 11 January 2010 21:25 UTC www.tektonics.org [Source type: Original source]

^ The inverse temperature is proportional to the change in entropy which results from the addition of one quantum of energy .
  • ACM Sigplan Notices 29, 4 (Apr 1994), 58-63. 10 January 2010 17:12 UTC www.pipeline.com [Source type: FILTERED WITH BAYES]

.As an example of one of the few cases where a complete solution is possible, we may take the comparatively simple case equation (17), already considered, which is approximately true for the majority of vapours at moderate pressures.^ We may take equation (17) as a practical example of the thermodynamical principles already given.

^ As an example of one of the few cases where a complete solution is possible, we may take the comparatively simple case equation (17), already considered, which is approximately true for the majority of vapours at moderate pressures.

^ Lesser inventors, e.g., less dedicated or determined, tend to give up prematurely for one reason or another, and thus a possible solution may be missed, and potential progress impeded for who knows how long.
  • Patent Law Blog (Patently-O): CAFC Rejects Patent on Invention to Overcome the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.patentlyo.com [Source type: FILTERED WITH BAYES]

.Writing formulae (3r) and (33) for the energy and entropy with indeterminate constants A and B, instead of taking them between limits, we obtain the following expressions for the thermodynamic functions in the case of the vapour: " =Solog e 0 - R log e p - ncp/D+A". E"=s:0 - ncp+B"..^ In the case of a solid or a liquid, the latent heat of isothermal expansion may often be neglected, and if the specific heat, s, be also taken as constant, we have simply 0-00 =s log e0/00.

^ Entropy is an extensive state function that accounts for the effects of irreversibility in thermodynamic systems.
  • Jeff's Lunchbreak: Creation Museum/Creationist Rule of Thumb with the 2nd Law of Thermodynamics 11 January 2010 21:25 UTC www.jefflewis.net [Source type: Original source]

^ Evolution as Described by the Second Law of Thermodynamics By viewing evolution as the motion of energy flows toward a stationary state (entropy), evolution can be explained by the second law of thermodynamics, a law which conventionally describes physical systems.
  • 'Evolution as Described by the Second Law of Thermodynamics' by PhysoOrg - RichardDawkins.net 11 January 2010 21:25 UTC richarddawkins.net [Source type: FILTERED WITH BAYES]

.F" =S 0 0 - (n+1)cp+bp+B„ dG"/dO (p
const) =0" = dJ"/dB (v const)..^ F" =S 0 0 - (n+1)cp+bp+B„ dG"/dO (p const) =0" = dJ"/dB (v const)..

.(39) dG"/dp (D const) =v, dJ"/dv (0 const) = p. (40) And all the properties of the substance may be expressed in terms of G or J and their partial differential coefficients.^ The properties define the state of the substance even though not all of them are independent.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ And all the properties of the substance may be expressed in terms of G or J and their partial differential coefficients.

^ Assuming the function G to be expressed in terms of p and 0, this condition represents the relation between p and 0 corresponding to equilibrium between the two states, which is the solution of the relation ( v" - v')dp/dO=L/D, (5).

.The values of the corresponding functions for the liquid or solid cannot be accurately expressed, as the theoretical variation of the specific heat is unknown, but if we take the specific heat at constant pressure
s to be approximately constant, and observe the small residual variation dh of the total heat, we may write F'=s'D+dh+B'. 4)' =s'loge0+d4)+A'..^ Specific heat of gas at constant volume.

^ S, Specific heat of gas at constant pressure.

^ (I I) This expression shows that the rate of variation of the total heat with temperature at constant pressure is equal to the specific heat at constant pressure.

.G' =s'e(i - log e 0) +(dh - Dd4) - A'D+B'.
where do is the corresponding residual variation of 0', and is easily calculated from a table of values of h. To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G
and G". Rearranging the terms, and dividing throughout by 0, we obtain an equation of the form R log ep= A - B/D - (s' - So)loge0+(c - b)p/D+(dh/D - d4)) (44) in which B=B" - B', and A = A'+s' - So.^ To find the border curve of equilibrium between the two states, giving the saturation pressure as a function of the temperature, we have merely to equate the values of G and G".

^ Units (Temperature; Pressure; Denstiy; Energy; Velocity; Viscosity; Surface Tension); Type of Data (Isothermal Properties; Isobaric Properties; Isochoric Properties; Saturation Properties)..."
  • Martindale's Calculators On-Line Center: Chemistry Center: R-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

^ The advantage is that cycle calculations can be done easily on a computer using simple equations.
  • Second law Analysis of Gas Turbines...Ben Wiens...innovation consultant...innovating through synergy...value innovation, simple, combined, heat, exchange, recuperated, fuel, cell, solid, oxide, engine, energy, thermodynamics, formulas, efficiency, combustion, conversion, enthalpy, entropy, exergy, availability, cogeneration, recuperation, chemical, looping, westinghouse, rolls, royce, solar, saturn, siemens, ge, steam, temperature, carnot, computer 11 January 2010 21:25 UTC www.benwiens.com [Source type: Academic]

.The value of A is determined by observing the value of Do at some known pressure po, e.g.^ The value of A is determined by observing the value of Do at some known pressure po, e.g.

^ The value of the specific heat S at constant pressure can always be determined by experiment, and in practice is one of the most important thermodynamical properties of a substance.

^ It is generally taken as constant, but its value at moderate pressures is difficult to determine.

at the boiling-point. The value of B is determined by observing the latent heat, Lo = F"o - F'0, which gives B =B" - B' =L0+(s' - So)00+(n+r)copo - bpo+dho (45) This constant may be called the absolute latent heat, as it expresses the thermal value of the change of state in a manner independent of temperature.
.The term (dh/0 - d4)) depending on the variation of the specific heat of the liquid may be made very small in the case of water by a proper choice of the constant s'. It is of the same order as the probable errors of observation, and may be neglected in.^ It is of the same order as the probable errors of observation, and may be neglected in.

^ Specific heat of gas at constant volume.

^ S, Specific heat of gas at constant pressure.

practice. .(See Vaporization, § 16.) The expression for R logp for an imperfect gas of this type differs from that for a perfect gas only by the addition of the term (c - b) p/D. This simple result is generally true, and the corresponding expressions for G" and J" are valid, provided that c - b in formula (17) is a function of the temperature only.^ The advantage of this type of equation is that c is a function of the temperature only.

^ A complete set of simple formulas for analyzing a gas turbine are provided.
  • Second law Analysis of Gas Turbines...Ben Wiens...innovation consultant...innovating through synergy...value innovation, simple, combined, heat, exchange, recuperated, fuel, cell, solid, oxide, engine, energy, thermodynamics, formulas, efficiency, combustion, conversion, enthalpy, entropy, exergy, availability, cogeneration, recuperation, chemical, looping, westinghouse, rolls, royce, solar, saturn, siemens, ge, steam, temperature, carnot, computer 11 January 2010 21:25 UTC www.benwiens.com [Source type: Academic]

^ The expression for R logp for an imperfect gas of this type differs from that for a perfect gas only by the addition of the term ( c - b) p/D. This simple result is generally true, and the corresponding expressions for G" and J" are valid, provided that c - b in formula (17) is a function of the temperature only.

.It is not necessary to suppose that c varies inversely as the nth power of the temperature, and that b is constant, as assumed in deducing the expressions for cp, E, and F. Although the value of G in any case cannot be found without that of 0, and although the consideration of the properties of the thermodynamic potential cannot in any case lead to results which are not directly deducible from the two fundamental laws, it affords a convenient method of formal expression in abstract thermodynamics for the condition of equilibrium between different phases, or the criterion of the possibility of a transformation.^ The laws of thermodynamics, by and large, cannot be changed.
  • FARK.com: (4742207) In this economy, we obey the laws of thermodynamics 11 January 2010 21:25 UTC www.fark.com [Source type: Original source]

^ Thermodynamics is based chiefly on two laws.
  • The Second Law of Thermodynamics 10 January 2010 17:12 UTC www.irfi.org [Source type: FILTERED WITH BAYES]

^ It is not necessary to suppose that c varies inversely as the nth power of the temperature, and that b is constant, as assumed in deducing the expressions for cp, E, and F. Although the value of G in any case cannot be found without that of 0, and although the consideration of the properties of the thermodynamic potential cannot in any case lead to results which are not directly deducible from the two fundamental laws, it affords a convenient method of formal expression in abstract thermodynamics for the condition of equilibrium between different phases, or the criterion of the possibility of a transformation.

.For such purely abstract purposes, the possibility of numerical evaluation of the function is of secondary importance, and it is often possible to make qualitative deductions with regard to the general nature of a transformation without any knowledge of the actual form of the function.^ For such purely abstract purposes, the possibility of numerical evaluation of the function is of secondary importance, and it is often possible to make qualitative deductions with regard to the general nature of a transformation without any knowledge of the actual form of the function.

^ That heat can then be put to a useful purpose, such as to power a car, and in doing that we transform (part of ) the heat into work.
  • Approaching the world’s environmental problems through the Second Law (Entropy Law) of Thermodynamics - Encyclopedia of Earth 11 January 2010 21:25 UTC www.eoearth.org [Source type: FILTERED WITH BAYES]

^ I actually still find it hard to believe that such an 'ignorance' on your part really exists, and wonder whether it is not feigned, for purposes thus far unknown to me.
  • Discussion with a Creationist aboutthe Second Law of Thermodynamics 11 January 2010 21:25 UTC www.fred.net [Source type: Original source]

.A more common method of procedure, however, is to infer the general relations of the thermodynamic potential from a consideration of the phenomena of equilibrium.^ A more common method of procedure, however, is to infer the general relations of the thermodynamic potential from a consideration of the phenomena of equilibrium.

^ The most important and most useful of the relations between the thermodynamical properties of a substance may be very simply deduced from a consideration of the indicator diagram by a geometrical method, which is in many respects more instructive than the analytical method generally employed.

^ Prigogine has developed a more general formulation of the laws of thermodynamics which includes nonlinear, irreversible processes such as autocatalytic activity.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.As it would be impossible within the limits of this article to illustrate or explain adequately the applications which have been made of the principles of thermodynamics, it has been necessary to select such illustrations only as are required for other reasons, or could not be found elsewhere.^ As it would be impossible within the limits of this article to illustrate or explain adequately the applications which have been made of the principles of thermodynamics, it has been necessary to select such illustrations only as are required for other reasons, or could not be found elsewhere.

^ A more complete and more elaborate treatment of the subject will be found in foreign treatises, such as those of Clausius, Zeuner, Duhem, Bertrand, Planck and others.

^ The object of the present article is to illustrate the practical application of the two general principles - (I) Joule's law of the equivalence of heat and work, and (2) Carnot's principle, that the efficiency of a reversible engine depends only on the temperatures between which it works; these principles are commonly known as the first and second laws of thermodynamics.

.For fuller details and explanations of the elements of the subject, the reader must be referred to general treatises such as Baynes's Thermodynamics (Oxford), Tait's Thermodynamics (Edinburgh), Maxwell's Theory of Heat (London), Parker's Thermodynamics (Cambridge), Clausius's Mechanical Theory of Heat (translated by Browne, London), and Preston's Theory of Heat (London).^ For fuller details and explanations of the elements of the subject, the reader must be referred to general treatises such as Baynes's Thermodynamics (Oxford), Tait's Thermodynamics (Edinburgh), Maxwell's Theory of Heat (London), Parker's Thermodynamics (Cambridge), Clausius's Mechanical Theory of Heat (translated by Browne, London ), and Preston's Theory of Heat (London).

^ I. The name thermodynamics is given to that branch of the general science of Energetics which deals with the relations between thermal and mechanical energy, and the transformations of heat into work, and vice versa.

^ A more complete and more elaborate treatment of the subject will be found in foreign treatises, such as those of Clausius, Zeuner, Duhem, Bertrand, Planck and others.

.One or two chapters on the subject are also generally included in treatises on the steam engine, or other heat engines, such as those of Rankine, Perry or Ewing.^ One or two chapters on the subject are also generally included in treatises on the steam engine, or other heat engines, such as those of Rankine, Perry or Ewing.

^ For fuller details and explanations of the elements of the subject, the reader must be referred to general treatises such as Baynes's Thermodynamics (Oxford), Tait's Thermodynamics (Edinburgh), Maxwell's Theory of Heat (London), Parker's Thermodynamics (Cambridge), Clausius's Mechanical Theory of Heat (translated by Browne, London ), and Preston's Theory of Heat (London).

^ A more complete and more elaborate treatment of the subject will be found in foreign treatises, such as those of Clausius, Zeuner, Duhem, Bertrand, Planck and others.

.Of greater interest, particularly from a historical point of view, are the original papers of Joule, Thomson and Rankine, some of which have been reprinted in a collected form.^ Of greater interest, particularly from a historical point of view, are the original papers of Joule, Thomson and Rankine, some of which have been reprinted in a collected form.

^ Dear Alper, thanks for pointing out the interesting paper of Wang et al..
  • thermodynamics of nanoscale small systems | iMechanica 11 January 2010 21:25 UTC www.imechanica.org [Source type: FILTERED WITH BAYES]

^ Throughout Chapters 7-9 we have analyzed the problems of complexity and the origin of life from a thermodynamic point of view.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

.A more complete and more elaborate treatment of the subject will be found in foreign treatises, such as those of Clausius, Zeuner, Duhem, Bertrand, Planck and others.^ A more complete and more elaborate treatment of the subject will be found in foreign treatises, such as those of Clausius, Zeuner, Duhem, Bertrand, Planck and others.

^ But his point is to argue for nuclear generation of hydrogen, and subjects peripheral to his mission, such as oil depletion, get careless treatment.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ Look at the millions of fossils of other creatures that are extant, with more found every day.
  • Thermodynamics 10 January 2010 17:12 UTC mwillett.org [Source type: Original source]

.Alphabetical Index of Symbols Employed.^ Alphabetical Index of Symbols Employed.

.0,
Thermodynamic or absolute temperature.^ Thermodynamic or absolute temperature.

^ The thermodynamic entropy S is defined by the relation Δ S = Δ Q / T, where Δ Q is the amount of heat absorbed in a reversible process, and T is the absolute temperature at which the process is occurring.
  • On the Relation between Thermodynamic and Configurational Entropy, and the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.foundalis.com [Source type: Original source]

^ The third law of thermodynamics (page 318) The entropy of a system approaches zero as its temperature approaches absolute zero.

0, Entropy. Section 13.
b, Covolume of molecules of gas. Equation (17).
.c, co, Co-aggregation volume per unit mass.^ V =RD/p, Ideal volume of gas per unit mass.

^ Co-aggregation volume per unit mass.

^ E, Intrinsic energy per unit mass.

Equation (17). .e, Base of Napierian logarithms.^ Base of Napierian logarithms.

.E, Intrinsic energy per unit mass.^ An intensive property can be derived from every extensive property by considering the extensive property per unit mass or mole of the substance.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ Oil has a higher energy content per unit weight and burns at a higher temperature than coal; it is easier to transport, and can be used in internal combustion engines.
  • Human and natural systems oppose the second law of thermodynamics byimporting inputs for replacement and maintenance 11 January 2010 21:25 UTC www.dieoff.org [Source type: Original source]

^ "The total solar energy absorbed by Earth's atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) per year.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

Section 2.
.F= E+pv, Total heat.^ The total heat with which we are actually concerned in the working of a steam engine is the total heat as here defined, and not the total heat as defined by Regnault, which, however, differs from ( E+pv ) only by a quantity which is inappreciable in ordinary practice.

^ In this case the condition of flow is simply that of constant total heat, or in symbols, d(E+pv) =0.

^ Since dE=dH - pdv, we have evidently for the variation of the total heat from the second expression (8), dF=d(E + pv) =dH+vdp=Sde - (Odv/de - v)dp .

Section 7.
.G, J, Thermodynamic potential functions.^ G, J, Thermodynamic potential functions.

^ This function is also called the " thermodynamic potential at constant volume " from the analogy with the condition of minimum potential energy as the criterion of stable equilibrium in statics .

Section 15.
.H, Quantity of heat (in mechanical units).^ The entropy transport rate associated with heat transfer at a boundary per unit time t with heat-transfer rate q/t and uniform temperature T is defined by the quantity (q/t)/T, and this quantity has the same sign convention as the heat-transfer.
  • IoHT :: 110+ Variations of the Second Law of Thermodynamics 11 January 2010 21:25 UTC www.humanthermodynamics.com [Source type: Academic]

^ (I) in which E 0 represents the quantity of energy originally present in the body, and all the quantities are supposed, as usual, to be expressed in mechanical units.

^ The units of heat (energy):       [J] = [VC] (electrical work) = [Nm] (mechanical work) J = Joule; V = voltage; C = charge; N = Newton; m = meter .
  • Thermodynamics and solution behavior of macromolecules 10 January 2010 17:12 UTC www.whatislife.com [Source type: Academic]

Section 2.
.K, k, Adiabatic and isothermal elasticities.^ If we write K for the adiabatic elasticity , and k for the isothermal elasticity, we obtain S/s = ECÆF = K/k.

^ K, k, Adiabatic and isothermal elasticities.

Equation (7).
.L, Latent heat of fusion or vaporization.^ L, Latent heat of fusion or vaporization .

Equation (5).
M, Molecular weight. Section 8.
m, .Mass of substance or molecule.^ Mass of substance or molecule.

n, Index in expression for c. Equation (17).
p, Pressure of fluid. po, Initial pressure.

R= S

so, Constant in gas-equation (17).
.S, Specific heat of gas at constant pressure.^ There is a specific physical energy requirement to lift oil (and gas under less pressure) out of the ground.
  • The Oil Drum: Canada | In this house, we obey the laws of thermodynamics! 11 January 2010 21:25 UTC canada.theoildrum.com [Source type: FILTERED WITH BAYES]

^ When valve 3 is opened, this gas will expand, pushing back the right piston against the constant external pressure of 1 atm, until the gas pressure is 1.00 atm.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

^ Heat always flows spontaneously from a hotter reservoir to a colder reservoir until there is no longer a temperature difference or gradient; gas will always flow from high pressure to low pressure until there is no longer a pressure difference or gradient.
  • Schneider and Kay, 1994 11 January 2010 21:25 UTC www.nesh.ca [Source type: Academic]

So, Limiting value of S when p=o. Section 12.
.s, Specific heat of gas at constant volume.^ S, Specific heat of gas at constant pressure.

^ Specific heat of gas at constant volume.

^ In the case of a solid or a liquid, the latent heat of isothermal expansion may often be neglected, and if the specific heat, s, be also taken as constant, we have simply 0-00 =s log e0/00.

so, Limiting value of s when p=o. Section 12.
.s', s", Specific heat under other conditions.^ The insulation is important because, under these conditions, the heat out term R e will be multiplied by 1 T o /T o = 0 , which would not be the case if heat leaked out the sides at higher temperatures.
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ Expansion or compression under the condition of heat-insulation, represented by curves called Adiabatics, such as BAZ or CDZ', which are necessarily steeper than the isothermals.

^ Under certain conditions, however, heat conduction may occur by a heat-convection current---the coordinated movement of many gas molecules.
  • Thermodynamics of Living Systems 11 January 2010 21:25 UTC www.evanwiggs.com [Source type: Academic]

Equation (5). .U, Kinetic energy of flow of fluid.^ U, Kinetic energy of flow of fluid.

^ If we consider any short length of the stream bounded by two imaginary cross-sections A and B on either side of the plug, unit mass of the fluid in passing A has work, p'v', done on it by the fluid behind and carries its energy, E'+ U', with it into the space AB, where U' is the kinetic energy of flow.

^ As the section of the tube varies, the change of kinetic energy of flow, dU, is represented by The flow in this case is reversible, and the state of the fluid is the same at points where the section of the tube is the same.

Section To.
it, Mean velocity of gaseous molecules. Section 8.
.V =RD/p, Ideal volume of gas per unit mass.^ Show that under conditions of standard pressure and temperature, the volume of a sample of an ideal gas depends only on the number of molecules in it.

^ For the first time we have an interpretation for the temperature based on a microscopic description of matter: in a monoatomic ideal gas, the temperature is a measure of the average kinetic energy per molecule.

^ The number of moles of gas was obtained by applying the ideal gas law to the initial pressure, volume, and temperature conditions.
  • Appendix F: Some Additional Aspects of Thermodynamics 11 January 2010 21:25 UTC www.wpi.edu [Source type: Academic]

Equation (17). v, .Specific volume of fluid, reciprocal of density.^ In the case of a simple compressible substance, one in which surface effects, electromagnetic effects, etc., are unimportant, h = u + Pv, where P is the total pressure of the system and v is the specific volume (the reciprocal of density).
  • Appendix I 10 January 2010 17:12 UTC dematerialism.net [Source type: FILTERED WITH BAYES]

^ Properties of Water & Steam Properties Calculator OUTPUT values include: "...Enthalpy; Internal Energy; Entropy; Specific Volume; Density; Isobaric Heat Capacity; etc..."
  • Martindale's Calculators On-Line Center: Mechanical Engineering: S-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]
  • Martindale's Calculators On-Line Center: Chemistry Center: R-Z - Databases, Courses, Textbooks, Lessons, Manuals, Guides, Publications, Technical Reports, Videos, Movies, Calculators, Spreadsheets, Applets, Animations, etc. 10 January 2010 17:12 UTC www.martindalecenter.com [Source type: Academic]

.W, External work done by fluid.^ W, External work done by fluid.

(H. L. C.)


Wikibooks

Up to date as of January 23, 2010

From Wikibooks, the open-content textbooks collection

The Microcanonical Ensemble

  1. States of a Brick
  2. Second Law of Thermodynamics
  3. Microcanonical Ensemble
  4. Thermodynamic Temperature

The Canonical Ensemble

  1. Two Bricks in Thermal Contact
  2. Partition Function
  3. Specific Heat
  4. Entropy and Heat Conduction

The Grand Canonical Ensemble

  1. Chemical Potential
  2. Grand Canonical Wnsemble
  3. Fermi and Bose Statistics

Critical Phenonomena

  1. Phase Transitions

The Ideal Gas and Heat Engines

  1. Ideal Gas
  2. Slow and Fast Expansions
  3. Heat Engines
  4. Perpetual Motion Machines

Further Reading


Citable sentences

Up to date as of December 29, 2010

Here are sentences from other pages on Thermodynamics, which are similar to those in the above article.








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