Iodine pentoxide is a white solid. It breaks down to iodine and oxygen when heated. It reacts with carbon monoxide to make carbon dioxide and iodine. It is a strong oxidizing agent. It reacts with water to make iodic acid.
Iodine pentoxide is made by heating iodic acid to 200 °C (392 °F) in dry air.
It is used to see how much carbon monoxide is in a sample of gas.