Source: Extra Practice

To prevent rusting, iron articles are often coated with a layer of paint or grease. This method works by:

Options

Option A

Increasing the temperature of the iron.

Option B

Changing the chemical composition of iron.

Option C is correct

Preventing contact between iron, oxygen, and water.

Option D

Making the iron softer.

Explanation

Rusting is a chemical reaction that requires the presence of both oxygen and water (or moisture) in contact with iron. Coating iron articles with paint or grease creates a protective barrier that physically separates the iron surface from the oxygen and water in the atmosphere. By preventing this essential contact, the chemical reaction of rusting cannot occur, thus protecting the iron. This method does not change the iron's chemical composition, temperature, or softness to prevent rust.