Iodine is an essential element needed for life ... He then discovered that the vapor would condense into deep violet crystals on cold surfaces. At the time, Courtois did not realize he had ...

(Left) Elemental iodine (Middle, Right ... When the iodine is gently heated, it sublimes (sublimates) and the gas forms extremely pure iodine crystals that collect on the cold test tube. Photo credit: ...

Iodized salt is intended to supply us with the chemical element iodine ... additive even more common than iodine is some anti-caking agent, to keep the salt crystals from sticking together ...