Barium cations Ba2+ Peroxide anions O2−2 | |
| Names | |
|---|---|
| IUPAC name barium peroxide | |
| Other names Barium binoxide, Barium dioxide | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
| ECHA InfoCard | 100.013.754 |
| EC Number |
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PubChem CID | |
| RTECS number |
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| UNII | |
| UN number | 1449 |
CompTox Dashboard (EPA) | |
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| Properties | |
| BaO2 | |
| Molar mass |
|
| Appearance | Grey-white crystalline solid (anhydrous) Colorless solid (octahydrate) |
| Odor | Odorless |
| Density |
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| Melting point | 450 °C (842 °F; 723 K) |
| Boiling point | 800 °C (1,470 °F; 1,070 K) (decomposes to BaO & O2. [1] ) |
| |
| Solubility | dissolves with decomposition in acid |
| −40.6×10−6 cm3/mol | |
| Structure | |
| Tetragonal [2] | |
| D174h, I4/mmm, tI6 | |
| 6 | |
| Hazards | |
| GHS labelling: | |
| | |
| Warning | |
| H272, H302, H332 | |
| P210, P220, P221, P261, P264, P270, P271, P280, P301+P312, P304+P312, P304+P340, P312, P330, P370+P378, P501 | |
| NFPA 704 (fire diamond) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Barium peroxide is an inorganic compound with the formula Ba O 2. This white solid (gray when impure) is one of the most common inorganic peroxides, and it was the first peroxide compound discovered. Being an oxidizer and giving a vivid green colour upon ignition (as do all barium compounds), it finds some use in fireworks; historically, it was also used as a precursor for hydrogen peroxide. [3]
Barium peroxide consists of barium cations Ba2+ and peroxide anions O2−2. The solid is isomorphous to calcium carbide, CaC2.
Barium peroxide arises by the reversible reaction of O2 with barium oxide. The peroxide forms around 500 °C (932 °F) and oxygen is released above 820 °C (1,510 °F). [1]
This reaction is the basis for the now-obsolete Brin process for separating oxygen from the atmosphere. Other oxides, e.g. Na2O and SrO, behave similarly. [4] [ page needed ]
In another obsolete application, barium peroxide was once used to produce hydrogen peroxide via its reaction with sulfuric acid: [3]
The insoluble barium sulfate is filtered from the mixture.