Question

Define anodizing. How is it done?

Answer 1

Anodizing is one of the methods used for preventing rusting. During anodizing process, dilute acid is taken into an electrolytic cell and aluminium article is dipped in it as the anode. On passing an electric current the hydrogen gas is released at the cathode and oxygen gas is released at the anode. A reaction of aluminium with oxygen occurs at the anode and a protective layer of hydrated aluminium oxide is formed on the metal surface.