Copper(II) oxide is a chemical compound with the formula CuO. It consists of copper in a +2 oxidation state and oxygen. This black solid is commonly used in various applications, including as a pigment in ceramics and glass, and as a precursor for producing other copper compounds. In addition to its industrial uses, copper(II) oxide is also studied in laboratories for its properties and reactions. It can be formed by heating copper in the presence of oxygen or by thermal decomposition of copper(II) carbonate. Its ability to conduct electricity makes it useful in electronic applications.