CBSE Class 12-science Answered

Dear Student,

• Corrosion slowly coats the surfaces of metallic objects with oxides or other salts of the metal.

• It causes enormous damage to buildings, bridges, ships and to all objects made of metals especially that of iron.

• In corrosion, a metal is oxidized by loss of electrons to oxygen and formation of oxides.

• Corrosion of iron (commonly known as rusting) occurs in presence of water and air. 

So, the factors which affect corrosion are: humidity, presence of air, temperature.

• At a particular spot of an object made of iron, oxidation takes place and that spot behaves as anode and we can write the reaction,