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प्रश्न
Classify the following as chemical or physical change:
Burning of paper and wood
पर्याय
Chemical change
Physical change
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उत्तर
Chemical change
Explanation:
Burning paper is a chemical change since the combustion products, carbon dioxide, water vapours, smoke, and ash, cannot be turned back into paper or wood using any physical means.
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संबंधित प्रश्न
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| List I | List II |
| 1. Expansion of a steel rod on heating | A: Physical change |
| 2. Rotting of eggs | B: Chemical change |
| 3. Milk turning sour | |
| 4. Tarnishing of copper | |
| 5. Separation of naphthalene from a mixture of naphthalene and sodium chloride. |
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(a) Melting
(b) Vaporisation
(c) Condensation
(d) Freezing
pertain to –
- Conversion of a liquid into a vapour or gas.
- Conversion of a liquid into a solid.
- Conversion of a solid into a liquid on heating.
