Iodine pentoxide

Jump to navigation Jump to search


Template:Chembox new

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

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

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.

References

  1. K. Selte and A. Kjekshus (1970). "Iodine oxides: part III, The crystal structure of I2O5". Acta Chemica Scandinavica. 24: 1912–1914.


Template:WH Template:WS