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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.
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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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