:Tellurium trioxide
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| verifiedrevid = 414397405
| ImageFile =
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| OtherNames = tellurium(VI) oxide
| Section1 = {{Chembox Identifiers
| CASNo = 13451-18-8
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = GC5SXW83F8
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 75319
| EC_number = 236-620-5
| PubChem = 83481
| InChI = 1/O3Te/c1-4(2)3
| InChIKey = IIXQANVWKBCLEB-UHFFFAOYAH
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/O3Te/c1-4(2)3
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = IIXQANVWKBCLEB-UHFFFAOYSA-N
| SMILES = O=[Te](=O)=O
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| Section2 = {{Chembox Properties
| Formula = TeO3
| MolarMass = 175.6 g/mol
| Appearance = yellow-orange crystals (α-TeO3)
| Density = 5.07 g/cm3, solid
| MeltingPtC = 430
| BoilingPt =
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| Section7 = {{Chembox Hazards
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Tellurium trioxide (TeO3) is an inorganic chemical compound of tellurium and oxygen. In this compound, tellurium is in the +6 oxidation state.
Polymorphs
There are two forms, yellow-red α-TeO3 and grey, rhombohedral, β-TeO3 which is less reactive.Inorganic Chemistry,Egon Wiberg, Arnold Frederick Holleman Elsevier 2001 {{ISBN|0-12-352651-5}}
α-TeO3 has a structure similar to FeF3 with octahedral TeO6 units that share all vertices.{{Greenwood&Earnshaw}}
Preparation
α-TeO3 can be prepared by heating orthotelluric acid, Te(OH)6, at over 300 °C. The β-TeO3 form can be prepared by heating α-TeO3 in a sealed tube with O2 and H2SO4.
α-TeO3 is unreactive to water but is a powerful oxidising agent when heated. With alkalis it forms tellurates.
α-TeO3 when heated loses oxygen to form firstly Te2O5 and then TeO2.
References
{{reflist}}
{{Tellurium compounds}}
{{Oxides}}
Category:Tellurium(VI) compounds
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