Rusting of iron is a chemical change that occurs when iron is exposed to moist air for a long time. It is characterized by the formation of a brown powdered mass on the iron, which is a mixture of iron oxides. Rusting is a type of corrosion that causes iron to become flaky and weak, degrading its strength, appearance, and permeability. The process of rusting involves the oxidation of iron, accompanied by the loss of electrons. The chemical formula for rusting is Fe(s) + O2(g) + H2O(l) → Fe2O3.xH2O(s) .

Factors that hasten the rusting of iron include exposure to moisture, oxygen, and acids. The process is usually accelerated by contact with less active metals, the strain in the iron, and the presence of rust itself. To prevent rusting of iron, various measures can be taken, such as painting, oiling, greasing, galvanizing, and electroplating.

In summary, rusting of iron is a chemical change that occurs when iron is exposed to moist air for a long time, leading to the formation of a brown powdered mass on the iron. The process involves the oxidation of iron, accompanied by the loss of electrons. Factors that hasten rusting include exposure to moisture, oxygen, and acids, while measures to prevent rusting include painting, oiling, greasing, galvanizing, and electroplating.