Question

give the mechanism of rusting and its prevention​

Answer 1

The H+ ions are obtained either from water or from acidic substances in water. The hydrogen atoms on the iron surface reduce dissolved oxygen. The ferrous ions are oxidized further by atmospheric oxygen to form rust. Therefore, this is the mechanism of rust with the chemical formula Fe2O3.

It is a very common method of preventing the rusting of iron. This can be done by dipping the metal to be protected in hot, molten zinc or by the process of electroplating. Zinc is a relatively cheap metal that sticks to steel easily. It also offers cathodic protection to the iron surface by acting as an anode.