Corrosion is the process in which metals are eaten up gradually by the action of air, moisture or a chemical on their surface. Corrosion is caused mainly by the oxidation of metals by the oxygen of the air.

Corrosion is the process in which metals are eaten up gradually by the action of air, moisture or a chemical on their surface. Corrosion is caused mainly by the oxidation of metals by the oxygen of the air.

1) Corrosion causes damage to car bodies.

1) Corrosion causes damage to car bodies.

2) Corrosion causes damage to bridges and Iron railings.

2) Corrosion causes damage to bridges and Iron railings.

3) Corrosion damages ships and other things made up of iron.

3) Corrosion damages ships and other things made up of iron.

4) Every year enormous amount of money is spent to replace damaged iron.

4) Every year enormous amount of money is spent to replace damaged iron.

Iron when exposed to moist air for a long time acquires a coating of a brown flaky substance called rust.

Iron when exposed to moist air for a long time acquires a coating of a brown flaky substance called rust.

Corrosion of different metals

Copper reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains green coat . This green substance is copper carbonate.

Copper reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains green coat . This green substance is copper carbonate.

Silver articles become black after sometime when exposed to air. This is because it reacts with sulphur in the air to form a coating of silver sulphide.

Silver articles become black after sometime when exposed to air. This is because it reacts with sulphur in the air to form a coating of silver sulphide.

1) The rusting of iron can be prevented by painting, oiling, galvanizing , chrome painting, greasing.

1) The rusting of iron can be prevented by painting, oiling, galvanizing , chrome painting, greasing.

2) Alloying is a very good method of improving the properties of a metal and preventing it from corrosion.

2) Alloying is a very good method of improving the properties of a metal and preventing it from corrosion.3) Galvanisation is a method of protecting steel and iron from rusting by Coating them with a thin layer of zinc.

3) Galvanisation is a method of protecting steel and iron from rusting by Coating them with a thin layer of zinc.