A halogen is a chemical element that forms a salt when it reacts with metal. … There are five halogens in the periodic table of chemical elements: fluorine, chlorine, bromine, iodine, and astatine. The halogens are all highly reactive, which means they’re quick to form bonds with other elements.
Chlorine is the best known of the halogen elements. The free element is widely used as a water-purification agent, and it is employed in a number of chemical processes. Table salt, sodium chloride, of course, is one of the most familiar chemical compounds. Fluorides are known chiefly for their addition to public water supplies to prevent tooth decay, but organic fluorides are also used as refrigerants and lubricants. Iodine is most familiar as an antiseptic, and bromine is used chiefly to prepare bromine compounds that are used in flame retardants and as general pesticides. In the past ethylene dibromide was extensively used as an additive in leaded gasoline.
These fire elements release substances that are toxic to humans in the form of toxic fumes but also cause corrosion of metals. Halogen-free plastics are safer, and products from them are particularly convenient to collection and escape routes (public spaces, railway stations, theaters, cinemas, shopping centers, etc.).
Վերգինե Խաչատրյան 