Iron(II) oxide, also known as ferrous oxide, is a chemical compound composed of iron and oxygen. Its chemical formula is FeO, and it typically appears as a black powder. This compound is formed when iron reacts with oxygen in a low-oxygen environment, and it is commonly found in nature as a mineral. Iron(II) oxide is used in various applications, including as a pigment in paints and coatings, and in the production of iron and steel. It can also serve as a reducing agent in chemical reactions. Additionally, it plays a role in the study of magnetism and materials science.