*** Welcome to piglix ***

Antimony pentoxide

Antimony pentoxide
Antimony-pentoxide-xtal-1979-3D-balls.png
Names
IUPAC name
(dioxo-λ5-stibanyl)oxy-dioxo-λ5-stibane
Other names
antimony(V) oxide
Identifiers
3D model (Jmol)
ChemSpider
ECHA InfoCard 100.013.853
PubChem CID
Properties
Sb2O5
Molar mass 323.517 g/mol
Appearance yellow powdery solid
Density 3.78 g/cm3, solid
Melting point 380 °C (716 °F; 653 K) (decomposes)
0.3 g/100 mL
Solubility insoluble in nitric acid
Structure
cubic
Thermochemistry
117.69 J/mol K
-1008.18 kJ/mol
Hazards
not listed
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
US health exposure limits (NIOSH):
PEL (Permissible)
TWA 0.5 mg/m3 (as Sb)
REL (Recommended)
TWA 0.5 mg/m3 (as Sb)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YesYN ?)
Infobox references

Antimony pentoxide (Sb2O5) is a chemical compound of antimony and oxygen. It always occurs in hydrated form, Sb2O5·nH2O. It contains antimony in the +5 oxidation state.

Antimony pentoxide has the same structure as the B form of niobium pentoxide and can be derived from the rutile structure, with antimony coordinated by six oxygens in a distorted octahedral arrangement. The SbO6 octahedra are corner- and edge-sharing.

The hydrated oxide is prepared by hydrolysis of antimony pentachloride; or by acidification of potassium hexahydroxoantimonate(V). It may also be prepared by oxidation of antimony trioxide with nitric acid.

It finds use as a flame retardant in ABS and other plastics, a flocculant in the production of titanium dioxide and is sometimes used in the production of glass, paint and adhesives.

It is also used as an ion-exchange resin for a number of cations in acidic solution including Na+ (especially for their selective retentions); and as a polymerization and oxidation catalyst.

The hydrated oxide is insoluble in nitric acid, but dissolves in concentrated potassium hydroxide solution to give potassium hexahydroxoantimonate(V), KSb(OH)6.

When heated at 700 °C the yellow hydrated pentoxide converts to an anhydrous white solid with a formula Sb6O13 containing both Sb(III) and Sb(V). Heating at 900 °C produces a white insoluble powder of Sb2O4 of both α and β forms. The β form consists of Sb(V) in octahedral interstices and pyramidal Sb(III) O4 units. In these compounds, Sb(V) atom is octahedrally coordinated to six –OH groups.


...
Wikipedia

...