α-Sb2O4 | |
Names | |
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IUPAC name
antimony(III,V) oxide | |
Identifiers | |
ECHA InfoCard | 100.014.161 |
PubChem CID |
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UNII | |
CompTox Dashboard (EPA) |
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Properties | |
SbO2; Sb2O4 | |
Molar mass | 153.7588; 307.5176 g/mol |
Appearance | white solid |
Density | 6.64 g/cm3 (orthorhombic form) [1] |
Melting point | > 930 °C (1,710 °F; 1,200 K) (decomposes) |
Boiling point | decomposes |
insoluble | |
Refractive index (nD) |
2.0 |
Structure | |
orthorhombic | |
Hazards | |
NFPA 704 (fire diamond) | |
NIOSH (US health exposure limits): | |
PEL (Permissible) |
TWA 0.5 mg/m3 (as Sb)[2] |
REL (Recommended) |
TWA 0.5 mg/m3 (as Sb)[2] |
Related compounds | |
Related compounds |
Antimony trioxide Antimony pentoxide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references |
Antimony tetroxide is an inorganic compound with the formula Sb2O4. This material, which exists as the mineral cervantite,[3] is white but reversibly yellows upon heating. The material, with empirical formula SbO2, is called antimony tetroxide to signify the presence of two kinds of Sb centers.[4]
Formation and structure
The material forms when Sb2O3 is heated in air:[5]
- Sb2O3 + 0.5 O2 → Sb2O4 ΔH = −187 kJ/mol
At 800 °C, antimony(V) oxide loses oxygen to give the same material:
- Sb2O5 → Sb2O4 + 0.5 O2 ΔH = −64 kJ/mol
The material is mixed valence, containing both Sb(V) and Sb(III) centers. Two polymorphs are known, one orthorhombic (shown in the infobox) and one monoclinic.[1] Both forms feature octahedral Sb(V) centers arranged in sheets with distorted Sb(III) centers bound to four oxides.
References
- 1 2 Amador, J.; Puebla, E. Gutierrez; Monge, M. A.; Rasines, I.; Valero, C. Ruiz (1988). "Diantimony Tetraoxides Revisited". Inorganic Chemistry. 27 (8): 1367–1370. doi:10.1021/ic00281a011.
- 1 2 NIOSH Pocket Guide to Chemical Hazards. "#0036". National Institute for Occupational Safety and Health (NIOSH).
- ↑ "Cervantite". Webminerals. Retrieved 2009-06-06.
- ↑ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 576. ISBN 978-0-08-037941-8.
- ↑ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
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