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Iodine pentoxide
Introduction
Iodine pentoxide is the chemical compound with the formula I2O5. This iodine oxide is the anhydride of iodic acid. It is produced by dehydrating iodic acid at 200 °C in a stream of dry air[1]:
- 2HIO3 → I2O5 + H2O
Structure
Structure
I2O5 is bent with an I-O-I angle of 139.2°, but the molecule has no mirror plane so its symmetry is not C2v. The terminal I-O distances are around 1.80 Å and the bridging I-O distances are around 1.95 Å[2].
Reactions
Reactions
Iodine pentoxide easily oxidises carbon monoxide to carbon dioxide at room temperature:
- 5CO + I2O5 → I2 + 5CO2
This reaction can be used to analyse the concentration of CO in a gaseous sample.
I2O5 forms iodyl salts, [IO2+], with SO3 and S2O6F2, but iodosyl salts, [IO+], with concentrated sulfuric acid.
