Sodium superoxide
| Names | |
|---|---|
|
IUPAC name
sodium(I) superoxide
|
|
| Other names
sodium superoxide
|
|
| Identifiers | |
12034-12-7 
|
|
| 3D model (Jmol) | Interactive image |
| PubChem | 61542 |
| RTECS number | WE2860010 |
|
|
|
|
| Properties | |
| NaO2 | |
| Molar mass | 54.9886 g/mol |
| Appearance | Yellow to orange crystalline solid |
| Density | 2.2 g/cm3 |
| Melting point | 551.7 °C (1,025.1 °F; 824.9 K) |
| Boiling point | Decomposes |
| Decomposes | |
| Basicity (pKb) | N/A |
| Structure | |
| cubic | |
| Thermochemistry | |
| 72.1 J/mol K | |
|
Std molar
entropy (S |
115.9 J/mol K |
|
Std enthalpy of
formation (ΔfH |
-260.2 kJ/mol |
|
Gibbs free energy (ΔfG˚)
|
-218.4 kJ/mol |
| Hazards | |
|
EU classification (DSD)
|
Corrosive |
| R-phrases | R35 |
| S-phrases | S1/2, S26, S37/39, S45 |
| NFPA 704 | |
| Flash point | Non flammable |
| Related compounds | |
|
Other anions
|
sodium oxide sodium peroxide |
|
Other cations
|
potassium superoxide |
|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
|
 (what is  ?) |
|
| Infobox references | |
Sodium superoxide is the inorganic compound with the formula NaO2. This yellow-orange solid is a salt of the superoxide anion. It is an intermediate in the oxidation of sodium by oxygen.
NaO2 is prepared by treating sodium peroxide with oxygen at high pressures:
It can also be prepared by careful oxygenation of a solution of sodium in ammonia:
The product is paramagnetic, as expected for a salt of the O−
2 anion. It hydrolyses readily to give a mixture of sodium hydroxide, oxygen and hydrogen peroxide. It crystallizes in the NaCl motif.
...
Wikipedia