Question

Rusting is:
A. Removal of impurities from an ore
B. Removal of zinc covering
C. Corrosion of iron
D. Initiation of corrosion

Answer 1

Hint: Rusting is the formation of a red or an orange coating on the surface of iron. It is caused due to the oxidation of iron metal.

Complete step by step answer:

Rusting is the formation of a layer of iron oxide above the parent iron metal. It is usually a reddish brown oxide formed by the reaction of iron and oxygen in the presence of water or air moisture. It is caused due to the oxidation of iron from 0 to +3 oxidation state. Surface rust is commonly flaky and friable, and it provides no protection to the underlying iron, unlike the formation of patina on copper surfaces. The chemical reaction demonstrating the process of rusting is given below.
\[4Fe + 3{O_2} + x{H_2}O \to 2F{e_2}{O_3}.x{H_2}O\]
The chemical formula of rust is: \[F{e_2}{O_3}.x{H_2}O\]. It is also known as hydrated iron (III) oxide. Rusting is the common term for corrosion of iron and its alloys, such as steel. Many other metals undergo similar corrosion, but the resulting oxides are not commonly called rust. After sufficient time, any iron body in the presence of water and oxygen can entirely convert into rust.

Hence, the correct answer is (C) corrosion of iron.

Additional information: To prevent the action of rust, rust resistant alloys are made. Stainless steel is an example of the same. Galvanization can prevent rust too.

Note: Rusting is a term used for corrosion of iron only. Often, it is invariably used for the corrosion of other metals too.