Cobalt(III) oxide

Cobalt(III) oxide[1]
IUPAC name cobalt(III) oxide, dicobalt trioxide
Other names cobaltic oxide, cobalt sesquioxide
Identifiers
CAS number	1308-04-9 Y
PubChem	24847893
Properties
Molecular formula	Co2O3
Molar mass	165.86 g/mol
Appearance	black powder
Density	5.18 g/cm3 [2]
Melting point	1900 °C
Structure
Crystal structure	Trigonal, hR30
Space group	R-3c, No. 167
Hazards
R-phrases	R22 R40 R43
S-phrases	S36/37
Y oxide (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Cobalt(III) oxide is the inorganic compound with the formula Co₂O₃. Although only two oxides of cobalt are well characterized, CoO and Co₃O₄,^[3] procedures claiming to give Co₂O₃ have been described. Thus treatment of Co(II) salts such as cobalt(II) nitrate with an aqueous solution of sodium hypochlorite (also known as bleach) gives a black solid.^[4] Some formulations of the catalyst hopcalite contain "Co₂O₃".

References

1. ^ Sigma-Aldrich product page
2. ^ Lide, David R., ed (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3. 
3. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Oxford: Butterworth-Heinemann. ISBN 0080379419. 
4. ^ Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. p. 1675.