Halogen (halogen) Refers to the Periodic System 7 (Ⅶ A) family non-metallic elements, including fluorine (Fluorine), Chlorine (Chlorine), Bromine (Bromine), iodine (Iodine), and astatine (Astatine) and other five elements, collectively known as halogens. As a typical halogen element most active non-metallic element in the self, always known as halogens |