The Full Wiki

Sodium oxide: Wikis


Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.


From Wikipedia, the free encyclopedia

Sodium oxide
Sodium oxide
Sodium oxide
IUPAC name
Other names Disodium oxide
CAS number 1313-59-3 Yes check.svgY
PubChem 73971
UN number 1825
Molecular formula Na2O
Molar mass 61.9789 g/mol
Appearance White solid
Density 2.27 g/cm3
Melting point


Boiling point

1950 °C decomposes

Solubility in water reacts violently to form NaOH
Crystal structure Antifluorite (face centered cubic), cF12
Space group Fm3m, No. 225
Tetrahedral (Na+); cubic (O2–)
Std enthalpy of
−414.2 kJ/mol
Standard molar
75.1 J mol−1 K−1
EU Index Not listed
Main hazards Corrosive, reacts violently with water
Flash point Non-flammable
Related compounds
Other anions Sodium sulfide
Sodium selenide
Sodium telluride
Other cations Lithium oxide
Potassium oxide
Rubidium oxide
Caesium oxide
Related sodium oxides Sodium peroxide
Sodium superoxide
Related compounds Sodium hydroxide
 Yes check.svgY (what is this?)  (verify)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Sodium oxide (SOX) is a chemical compound with the formula Na2O. It is used in ceramics and glasses. Treatment with water affords sodium hydroxide.

Na2O + H2O → 2 NaOH

The alkali metal oxides M2O (M = Li, Na, K, Rb) crystallise in the antifluorite structure. In this motif the positions of the anions and cations are reversed relative to their positions in CaF2, with sodium ions tetrahedrally coordinated to 4 oxide ions and oxide cubically coordinated to 8 sodium ions.[1][2]



Glass making

In the typical application, glass contains around 15% sodium oxide, the other components being silica (silicon dioxide) and lime (calcium oxide) at around 70% and 9%, respectively. The soda serves as a flux to lower the temperature at which the silica melts. Soda glass has a lower melting temperature vs pure silica, and has improved mechanical properties due to its slight increases in elasticity. These changes arise because the silicon dioxide and soda react to form sodium silicates of the general formula Na2[SiO2]x[SIO3].


Na2O forms when sodium is treated with oxygen.

4 Na + O2 → 2 Na2O

Burning sodium in air will produce Na2O and about 20% sodium peroxide Na2O2.

6 Na + 2 O2 → 2 Na2O + Na2O2

Pure Na2O can be prepared by reaction of liquid sodium with NaNO3.

10 Na + 2 NaNO3 → 6 Na2O + N2

Sodium Oxide is also used in street lights and highway lights. They produce a yellow colored light.


  1. ^ Zintl, E.; Harder, A.; Dauth B. (1934), "Gitterstruktur der oxyde, sulfide, selenide und telluride des lithiums, natriums und kaliums", Z. Elektrochem. Angew. Phys. Chem. 40: 588–93  
  2. ^ Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.

External links

Got something to say? Make a comment.
Your name
Your email address