Separating Metals from Metal Oxides

Metals react with oxygen in the air to produce metal oxides

• Oxidation and reduction involve the addition or removal of oxygen from a substance and are called redox reactions

• Oxidation is a reaction in which:

  • Oxygen is added to an element or a compound

• Reduction is a reaction in which:

  • Oxygen is removed from an element or a compound

• A common example is the reaction with red-brown copper metal to produce black copper oxide:

• 2Cu + O2 ⟶ 2CuO

• In this reaction copper metal has been oxidised since oxygen has been added to it

• Another example is the reaction of zinc oxide with carbon:

• ZnO + C ⟶ Zn + CO

• In this reaction the zinc oxide has been reduced since it has lost oxygen. The carbon atom has been oxidised since it has gained oxygen.