Iodates are a class of chemical compounds containing this group. Examples are sodium iodate (NaIO3), silver iodate (AgIO3), and calcium iodate (Ca(IO3)2). Iodates resemble chlorates with iodine instead of chlorine.
In acidic conditions, iodic acid is formed. Potassium hydrogen iodate (KH(IO3)2) is a double salt of potassium iodate and iodic acid and an acid as well. Iodates are used in the iodine clock reaction.
|Iodine oxidation state||-1||+1||+3||+5||+7|
Minerals containing essential iodate anions are very rare. They are almost exclusively known from the caliche deposits of Chile. The deposits stand for the main source of nitrates, but iodate- and chromate-bearing minerals are also present there. The most important iodate minerals are lautarite and brüggenite, but also copper-bearing iodates (e.g., salesite) are known. In the iodate minerals iodine is always pentavalent, i.e., present as the anions.
Thioethers can be oxidized to sulfoxides by periodate, and periodate is reduced to iodate