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प्रश्न
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.
उत्तर
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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| Column I | Column II | ||
| 1. | Burning of coal | a. | Rusting |
| 2. | Painting of a surface | b. | Evaporation |
| 3. | Dipping iron in the water | c. | Chemical change |
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