Iron chloride is a chemical compound made up of iron and chlorine. It typically appears as a yellowish-brown solid and can exist in two main forms: ferrous chloride (FeCl2) and ferric chloride (FeCl3). These forms differ in the oxidation state of iron, with ferrous chloride containing iron in a +2 state and ferric chloride containing it in a +3 state. Ferric chloride is commonly used in water treatment processes to remove impurities and as a coagulant. It is also utilized in the production of printed circuit boards and as a catalyst in various chemical reactions. Ferrous chloride is often used in the production of iron salts and as a reducing agent in chemical processes.