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Question
Distinguish physical and chemical changes.
Solution
1. Physical changes:
- No new substance is formed
- Reversible
- Change in physical properties like size, shape, state
- Melting of ice, tearing of paper freezing, evaporation vaporization
2. Chemical changes:
- New substance is formed
- Irreversible
- Change in properties of reactants and products
- Burning of paper, photosynthesis, digestion of food, rusting of iron
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