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Question
Classify the following as physical or chemical changes :
- Cooking of food
- Boiling of water
- Cutting of trees
- D0issolving salt in water
- Digestion of food
- Melting of ice
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Solution
- Cooking of food – Chemical change
- Boiling of water – Physical change
- Cutting of trees – Physical change
- Dissolving salt in water – Physical change
- Digestion of food – Chemical change
- Melting of ice- Physical change
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| 1. Burning of paper | A: Physical change |
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Higher order Thinking question
Boiling of water is a physical change; but boiling of egg is a chemical change. Why?
