2023 · Q39
In which one of the following cases do both physical and chemical changes take place?
General KnowledgeChemistry
- ABurning of candle.
- BFreezing of water.
- CCooking of food.
- DRusting of iron.
Explanation
Burning a candle involves both changes: melting of wax is a physical change, while combustion of the wax vapour with oxygen is a chemical change. Freezing of water is only a physical change, and rusting of iron only a chemical change, so the candle is the case where both occur.