71626-98-7

white crystalline lumps

Calcium iodide hydrate used in photography. It is also used in cat food as a source of iodine.

Dissolve the salt in acetone, which is then diluted and evaporated. This drying process is repeated twice, then the CaI2 is recrystallised from acetone/diethyl ether and stored over P2O5. It is very hygroscopic when anhydrous and is light sensitive [Cremlyn et al. J Chem Soc 528 1958]. The yellow hexahydrate has m 42o. It is soluble in H2O, MeOH, EtOH and Me2CO but insoluble in Et2O.