Sodium peroxide is an

inorganic compound An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds⁠that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorgan ...

with the formula Na₂ O₂. This yellowish solid is the product of sodium ignited in excess oxygen. It is a strong base. This

metal peroxide A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated wit ...

exists in several

hydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

s and peroxyhydrates including Na₂O₂·2H₂O₂·4H₂O, Na₂O₂·2H₂O, Na₂O₂·2H₂O₂, and Na₂O₂·8H₂O.Harald Jakob, Stefan Leininger, Thomas Lehmann, Sylvia Jacobi, Sven Gutewort. "Peroxo Compounds, Inorganic". ''Ullmann's Encyclopedia of Industrial Chemistry'', 2007, Wiley-VCH, Weinheim. . The octahydrate, which is simple to prepare, is white, in contrast to the anhydrous material.

Properties

Sodium peroxide crystallizes with hexagonal symmetry. Upon heating, the hexagonal form undergoes a transition into a phase of unknown symmetry at 512 °C. With further heating above the 657 °C boiling point, the compound decomposes to Na₂O, releasing O₂.Lewis, R. J. ''Sax's Dangerous Properties of Industrial Materials, 10th ed.'', John Wiley & Sons, Inc.: 2000. : 2 Na₂O₂ → 2 Na₂O + O₂

Preparation

Commercially, sodium peroxide is produced from the elements in a two-stage process. First sodium is oxidized to sodium oxide:Macintyre, J. E., ed. ''Dictionary of Inorganic Compounds,'' Chapman & Hall: 1992.E. Dönges "Lithium and Sodium Peroxides" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 979. : Subsequently, this oxide is treated with more oxygen: : This was the method by which the substance was discovered in 1810 by Joseph Louis Gay-Lussac and Louis Jacques Thénard, as well as how it was for the first time commercially made by

Hamilton Castner Hamilton Young Castner (September 11, 1858 – October 11, 1899) was an American industrial chemist. Biography He was born in Brooklyn, New York and educated at the Brooklyn Polytechnic Institute, then at the Columbia University School of Mi ...

in the 1890s. It may also be produced by passing ozone gas over solid

sodium iodide Sodium iodide (chemical formula NaI) is an ionic compound formed from the chemical reaction of sodium metal and iodine. Under standard conditions, it is a white, water-soluble solid comprising a 1:1 mix of sodium cations (Na+) and iodide anions ...

inside a

platinum Platinum is a chemical element; it has Symbol (chemistry), symbol Pt and atomic number 78. It is a density, dense, malleable, ductility, ductile, highly unreactive, precious metal, precious, silverish-white transition metal. Its name origina ...

palladium Palladium is a chemical element; it has symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1802 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas (formally 2 Pallas), ...

tube. The ozone oxidizes the sodium to form sodium peroxide. The

iodine Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a vi ...

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.

Uses

Sodium peroxide hydrolyzes to give

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula . It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly corrosive base (chemistry), ...

and

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usua ...

according to the reaction : Na₂O₂ + 2 H₂O → 2 NaOH + H₂O₂ 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 of ''Solozone'' and ''Flocool''.Lewis, R. J. ''Sax's Dangerous Properties of Industrial Materials, 10th ed.'', John Wiley & Sons, Inc.: 2000. 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 and

sodium carbonate Sodium carbonate (also known as washing soda, soda ash, sal soda, and soda crystals) is the inorganic compound with the formula and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water ...

: : Na₂O₂ + CO₂ → Na₂CO₃ + O₂ : Na₂O₂ + H₂O + 2 CO₂ → 2 NaHCO₃ + O₂ It is thus particularly useful in scuba gear, submarines, etc. Lithium peroxide and

potassium superoxide Potassium superoxide is an inorganic compound with the formula . It is a yellow paramagnetic solid that decomposes in moist air. It is a rare example of a stable salt of the superoxide anion. It is used as a scrubber, dehumidifier, and gene ...

have similar uses. Sodium peroxide was once used on a large scale for the production of

sodium perborate Sodium perborate are chemical compounds with chemical formula (H2O)x. Commonly encountered salts are the anhydrous form (x = 0) and as a hydrate, hexahydrate (x = 6). These two species are sometimes called, respectively, "monohydrate" or PBS-1 a ...

, but alternative routes to that cleaning agent have been developed.

References

External links

International Chemical Safety Card 1606
{{oxygen compounds Peroxides Sodium compounds Oxidizing agents