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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.
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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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संबंधित प्रश्न
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
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Copper carbonate
Select the correct answer for the following options:
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Explain the term chemical reaction with special reference to reactants and products.
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Higher order Thinking question
A very hot glass on putting in cold water cracks. What does this change indicate?
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What changes do you expect?
