Copper oxide

Copper forms two oxides, copper(I) oxide (cuprous oxide, Cu₂O) a red powder and copper(II) oxide (cupric oxide, CuO) a black powder. Cu₂O has some scientific uses, including use as a superconductor. CuO is the main product when copper is heated in air. The mineral cuprite, a red colored crystal, is copper(I) oxide.

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