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| Names | |
|---|---|
| IUPAC name Sodium peroxide | |
| Other names Flocool Solozone Disodium peroxide | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider |
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| ECHA InfoCard | 100.013.828 |
| EC Number |
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| RTECS number |
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| UNII | |
| UN number | 1504 |
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| Properties | |
| Na2O2 | |
| Molar mass | 77.98 g/mol |
| Appearance | yellow to white powder |
| Density | 2.805 g/cm3 |
| Melting point | 460 °C (860 °F; 733 K) (decomposes) |
| Boiling point | 657 °C (1,215 °F; 930 K) (decomposes) |
| Reacts | |
| Solubility | Soluble in acid Insoluble in base Reacts withethanol |
| −28.10·10−6 cm3/mol | |
| Structure | |
| hexagonal | |
| Thermochemistry | |
| 89.37 J/(mol·K) | |
Std molar entropy(S⦵298) | 95 J/(mol·K)[1] |
Std enthalpy of formation(ΔfH⦵298) | −515 kJ·mol−1[1] |
Gibbs free energy(ΔfG⦵) | −446.9 kJ/mol |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | Caustic, reacts with water and ethanol, oxidizer |
| GHS labelling: | |
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| Danger | |
| H271,H314 | |
| P210,P220,P221,P260,P264,P280,P283,P301+P330+P331,P303+P361+P353,P304+P340,P305+P351+P338,P306+P360,P310,P321,P363,P370+P378,P371+P380+P375,P405,P501 | |
| NFPA 704 (fire diamond) | |
| Flash point | Non-flammable |
| Safety data sheet (SDS) | External MSDS |
| Related compounds | |
Othercations | Lithium peroxide Potassium peroxide Rubidium peroxide Caesium peroxide |
| Sodium oxide Sodium superoxide Sodium ozonide | |
Related compounds | Sodium hydroxide Hydrogen peroxide |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Sodium peroxide is aninorganic compound with the formulaNa2O2. This yellowish solid is the product of sodium ignited in excess oxygen.[3] It is a strong base. Thismetal peroxide exists in severalhydrates and peroxyhydrates including Na2O2·2H2O2·4H2O, Na2O2·2H2O, Na2O2·2H2O2, and Na2O2·8H2O.[4] The octahydrate, which is simple to prepare, is white, in contrast to the anhydrous material.[5]
Sodium peroxide crystallizes with hexagonal symmetry.[6] Upon heating, the hexagonalform undergoes a transition into a phase of unknown symmetry at 512 °C.[7] With further heating above the 657 °C boiling point, the compound decomposes to Na2O, releasing O2.[8]
Commercially, sodium peroxide is produced from the elements in a two-stage process. First sodium is oxidized tosodium oxide:[7][9]
Subsequently, this oxide is treated with more oxygen:
This was the method by which the substance was discovered in 1810 byJoseph Louis Gay-Lussac andLouis Jacques Thénard, as well as how it was for the first time commercially made byHamilton Castner in the 1890s.[10]
It may also be produced by passing ozone gas over solidsodium iodide inside aplatinum orpalladium tube. The ozone oxidizes the sodium to form sodium peroxide. Theiodine can be sublimed by mild heating. The platinum or palladium catalyzes the reaction and is not attacked by the sodium peroxide.
The octahydrate can be produced by treating sodium hydroxide with hydrogen peroxide.[5]
Sodium peroxidehydrolyzes to givesodium hydroxide andhydrogen peroxide according to the reaction[9]
Sodium peroxide was used to bleach wood pulp for the production of paper and textiles. Presently it is mainly used for specialized laboratory operations, e.g., the extraction of minerals from various ores. Sodium peroxide may go by the commercial names ofSolozone[7] andFlocool.[8] In chemistry preparations, sodium peroxide is used as an oxidizing agent. It is also used as an oxygen source by reacting it with carbon dioxide to produce oxygen andsodium carbonate:
It is thus particularly useful in scuba gear, submarines, etc.Lithium peroxide andpotassium superoxide have similar uses.
Sodium peroxide was once used on a large scale for the production ofsodium perborate, but alternative routes to that cleaning agent have been developed.[4]
