This element is no longer available.
Iodine is a non-metallic, dark-grey/purple-black, lustrous, solid element. Iodine is the most electropositive halogen and the least reactive of the halogens even if it can still form compounds with many elements. Iodine sublime easily on heating to give a purple vapour. Iodine dissolves in some solvents, such as carbon tetrachloride and it is only slightly soluble in water. Iodine is used in medical treatment as tincture and iodioform, it is employed in the preparation of certain drugs and in the manufacture of some printing inks and dyes. Silver iodine is used in photography. Iodine is added to almost all the table salt and is used as a supplement to animal feed. It is also an ingredient of water purification tablets that are used for drinking water preparation.