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| Names | |
|---|---|
| IUPAC name Iodine pentoxide | |
| Other names Iodine(V) oxide Iodic anhydride | |
| Identifiers | |
3D model (JSmol) | |
| ChEBI | |
| ChemSpider |
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| ECHA InfoCard | 100.031.569 |
| UNII | |
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| Properties | |
| I 2O 5 | |
| Molar mass | 333.81 g/mol |
| Appearance | white crystalline solid[1] hygroscopic |
| Density | 4.980 g/cm3[1] |
| Melting point | 300 °C (572 °F; 573 K)[2] (decomposes) |
| Solubility | soluble in water andnitric acid; insoluble inethanol,ether andCS2 |
| −79.4·10−6 cm3/mol | |
| Thermochemistry | |
Std enthalpy of formation(ΔfH⦵298) | −173.0 kJ/mol |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | oxidizer |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Otheranions | iodine pentafluoride |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Iodine pentoxide is thechemical compound with theformula I2O5. Thisiodine oxide is theanhydride ofiodic acid, and one of the fewiodine oxides that is stable. It is produced by dehydrating iodic acid at 200 °C in a stream of dry air:[1]
I2O5 is bent with an I–O–I angle of 139.2°, but the molecule has no mirror plane so itssymmetry is C2 rather than C2v. The terminal I–O distances are around 1.80 Å and the bridging I–O distances are around 1.95 Å.[3]
Iodine pentoxide easily oxidisescarbon monoxide tocarbon dioxide at room temperature:
This reaction can be used to analyze the concentration of CO in a gaseous sample.
I2O5 forms iodyl salts, [IO2+], withSO3 andS2O6F2, but iodosyl salts, [IO+], with concentratedsulfuric acid.
Iodine pentoxide decomposes to iodine (vapor) and oxygen when heated to about 350 °C.[4]
