FeCl2, or iron(II) chloride, is a chemical compound made up of iron and chlorine. It consists of one iron atom and two chlorine atoms, giving it the formula FeCl2. This compound typically appears as a yellow-green solid and is soluble in water, forming a pale green solution. FeCl2 is commonly used in various applications, including water treatment, as a catalyst in chemical reactions, and in the production of other iron compounds. It can also serve as a reducing agent in organic synthesis, making it valuable in both industrial and laboratory settings.