1. APPLICATIONS of REDOX REACTIONS

2. ELECTROPLATING Electroplating is the use of electrolysis to apply a thin layer of one metal over another.

3. ELECTRO-REFINING of COPPER Electrolysis allows the dissolution of copper from the impure (blister) copper anode and deposition of pure copper on the copper cathode.

4. Reactions: At the cathode: Cu 2+ (aq) + 2e - → Cu (s) At the anode: Cu (s) → Cu 2+ (aq) + 2e -

5. EXTRACTION OF ALUMINIUM FROM BAUXITE Electrolysis of aluminium oxide dissolved in cryolite (Na 3 AlF 6 ) results in harvesting of pure aluminium.

6. Chemical reactions: At the cathode: Al 3+ + 3e - → Al (l) The liquid aluminium forms a layer of molten aluminium at the bottom of the cell. At the anode: 2O 2- → O 2(g) + 4e - oxygen reacts with the carbon electrode to form carbon dioxide.