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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.
Solution
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.
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