One example is the reduction of magnesium oxide to magnesium metal, which involves reacting magnesium oxide with carbon at 2000 degrees Celsius. Magnesium oxide is reduced (by losing oxygen) to form magnesium metal. The final compounds produced are magnesium metal and carbon monoxide. Another example is copper oxide being reduced to copper through heating it with hydrogen gas. In this process, the copper oxide loses oxygen to become a copper medal; the final products produced are copper and water.