Question

Why is the rusting of iron termed as a chemical change?

• A. It can be cleaned and the original substance can be recovered.
• B. A new substance is formed.
• C. It is a temporary change.
• D. It is a slow reaction.

Answer 1

The correct option is B

A new substance is formed.

Iron reacts chemically with the oxygen and the water vapuour present in air which converts iron to a different chemical substance. The shiny iron becomes dull and brown in colour. This is what we call rust.

Rust is nothing but iron oxide, a new substance formed out of the reaction. Hence, rusting of iron is a chemical change.