Assertion (A): Rusting of iron is a form of corrosion.
Reason (R): An iron rod does not corrode if it is coated with paint, oil or grease.
Choose the correct option.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Both (A) and (R) are correct, but (R) is not the correct explanation of (A).
Assertion (A): Rusting of iron is a form of corrosion. — Correct. Corrosion is the slow eating away of a metal by air, moisture or chemicals; for iron, in the presence of both air and water, it is called rusting.
Reason (R): An iron rod does not corrode if it is coated with paint, oil or grease. — Correct. The coating keeps air and moisture away from the iron. This is a way of preventing rusting; it does not explain why rusting is a kind of corrosion.