Green Lion Halogen Elements
Halogens are highly reactive in nature. Fluorine is the most reactive of all elements. Most elements react directly with chlorine, bromine and iodine, with decreasing reactivity going down the group, but often the reaction must be activated by heat or UV light. They have a number of important industrial and commercial applications, where their use in some chemicals has resulted in ozone depletion and in particular thinning of the ozone layer at high latitudes. The name for this group is in part derived from the Greek word Halos meaning salts.