What do you mean by corrosion? How can it be controlled ?

Explanation

Corrosion: The process of slow eating of metal due to attack of atmospheric gases on the surface of metals resulting into formation of compounds is called corrosion. Following methods are used to prevent metal corrosion:
(i) Barrier protection: By painting or greasing metal objects we can break contact between oxygen, water and metal.
(ii) Artificial protection: Metal surface which is to be protected may be covered with some other metal surface i.e. iron is covered with zinc layer to prevent it from rusting. This process is called galvanization.
(iii) Electrical protection: In this method metal ions are neutralised by electric current.. Iron article which we have to protect from rusting is connected to cathode.
(iv) By using antirust solutions: These are alkaline phosphates and alkaline chromates. These ions prevent oxidation of objects.