Question

Rusting of iron is ___________ change.

Answer 1

A chemical change is a change that alters the chemical composition of a substance.

These changes are generally irreversible and new substances will be formed. Here, rusting of iron ($\mathrm{Fe}$)is a chemical change, and the new substance formed is called rust (${\mathrm{Fe}}_2{\mathrm{O}}_3.{\mathrm{xH}}_2\mathrm{O}$). This is an irreversible reaction.

Hence, Rusting of iron is a chemical change.