Antimony (III, V) oxide

Crystal structure
__ Sb 3 + / 5 +      __ O 2−
General
Surname	Antimony (III, V) oxide
other names	Diantimony tetroxide Antimony dioxide Antimony (III) antimonate (V)
Ratio formula	Sb 2 O 4
Brief description	white solid
External identifiers / databases
CAS number 1332-81-6 12786-74-2 EC number 215-576-0 ECHA InfoCard 100.014.161 PubChem 74002 Wikidata Q206765
properties
Molar mass	307.51 g mol −1
Physical state	firmly
density	6.63 g cm −3 (orthorhombic) 6.72 g cm −3 (monoclinic)
Melting point	1050 ° C (decomposition)
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 302-331-315-319-335-411 P: 101-102-103-280-261-305 + 351 + 338-301 + 312-403 + 233-501
Thermodynamic properties
ΔH f 0	−907.5 kJ mol −1
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Antimony (III, V) oxide , also antimony (III) antimonate (V) or diantimony tetroxide , is an antimony compound with the empirical formula Sb ₂ O ₄ . It belongs to the oxide class . Diantimony tetroxide is a white powder that is yellow when heated and is insoluble in water.

Occurrence

Antimony (III, V) oxide occurs naturally in the form of the mineral cervantite . Find places are among others in Romania , Bolivia and Spain .

Extraction and presentation

Antimony (III, V) oxide forms are available in several ways. Antimony (V) oxide converts to diantimony tetroxide at 800 ° C with the release of oxygen. However, the connection does not melt.

${\displaystyle {\ce {2Sb2O5 -> 2Sb2O4 + O2 ^}}}$

Diantimony tetroxide is also formed from antimony (III) oxide when it is heated to over 500 ° C in air.

${\displaystyle {\ce {2Sb2O3 + O2 -> 2Sb2O4}}}$

properties

There are no tetravalent ions in antimony (III, V) oxide, rather it is a mixed oxide of antimony (III) and antimony (V) oxide. The frequently used name antimony (IV) oxide is therefore chemically incorrect.

Two modifications , α- and β-antimony (III, V) oxide are known. At a temperature of 1130 ° C, the α- converts to the β-form. α-Antimony (III, V) oxide crystallizes in the orthorhombic crystal system with the lattice parameters a = 5.43  Å , b = 4.81 Å and c = 11.78 Å as well as four formula units per unit cell . The β-form is monoclinic with the lattice parameters a = 12.06 Å, b = 4.84 Å, c = 5.38 Å and β = 104.56 °, as well as four formula units per unit cell.

There are layers of SbO ₅ octahedra that have a pentavalent antimony atom in the center. These are linked to one another via their corners. The layers are linked to one another via the trivalent antimony atoms.

Diantimony tetroxide is soluble in concentrated sulfuric acid and hydrochloric acid . In contrast, the compound does not dissolve in water or dilute acids and alkalis.

Individual evidence

1. ^ AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 , p. 820.
2. ↑ ^{a b c} J. Amador, E. Gutierrez Puebla, MA Monge, I. Rasines, C. Ruiz Valero: Diantimony Tetraoxides Revisited , in: Inorg. Chem. 1988 , 27 , 1367-1370, doi : 10.1021 / ic00281a011 .
3. ↑ ^{a b c} Entry on antimony oxides. In: Römpp Online . Georg Thieme Verlag, accessed on December 25, 2014.
4. ↑ ^{a b} Strem Chemicals: Antimony (IV) oxide (99.99% -Sb) PURATREM , accessed on December 27, 2019
5. ↑ M. Binnewies, E. Milke: Thermochemical Data of Elements and Compunds . 2nd Edition. Wiley-VCH, weinheim 2002, ISBN 3-527-30524-6 , pp. 829 .
6. ^ Paul Ramdohr , Hugo Strunz : Textbook of Mineralogy . 16th edition. Ferdinand Enke Verlag 1978, ISBN 3-432-82986-8 (p. 543).
7. ^ ^{A b c} A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 849.