What happens to copper oxide when heated?

There are two oxides of copper. Copper(I) oxide (cuprous oxide, Cu2O) , red color forms below 300 C; Copper(II) oxide (cupric oxide, CuO), brown,black oxide that forms above 300 C. Continued heating to 1326 C results in melting and at 2000C, it boils. Black and red copper oxides. read more

Heated copper metal reacts with oxygen to form the black copper oxide. Thecopper oxide can then react with the hydrogen gas to form the copper metal and water. read more

A clean copper surface will appear, well, copper colored. As it is heated, a layer of black copper oxide will form, thus changing its color. As the temperature increases, the oxide layer will get thicker, up to a point. Then the layer begins to decompose as the copper gives up the oxygen faster than it reacts. read more