Iodine pentafluoride is a colourless liquid with a pungent odour. The highly reactive IF5 (melting point 9.4 °C) is distillable at 100.5 °C without any decomposition. Decomposition commences at temperatures above 400 °C. In contact with water, iodine pentafluoride hydrolyses spontaneously forming hydrogen fluoride and iodic acid. Iodine pentafluoride is not soluble in mineral acids such as sulphuric acid and nitric acid; only a slow, regular formation of hydrogen fluoride takes place at the interface between the liquids. Iodine pentafluoride is soluble in some fluorinated solvents such as CCl3F or higher fluorinated hydrocarbons.