Question

Classify each of the following, as a physical or a chemical change. Give reasons.

(a) Drying of a shirt in the sun.

(b) Rising of hot air over a radiator.

(c) Burning of kerosene in a lantern.

(d) Change the colour of black tea by adding lemon juice to it.

(e) Churning of milk cream to get butter.

Answer 1

Physical changes because there is no change in chemical composition,

(a) Drying of a shirt in the sun.

(b) Rising of hot air over a radiator. 

(e) Churning of milk cream to get butter.

Chemical changes because new substances are formed.

(c) Burning of kerosene in a lantern.

(d) Change the colour of black tea by adding lemon juice to it.