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प्रश्न
Give three reasons why melting of wax, is considered a physical change while burning of a candle, a chemical change.
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उत्तर
Melting of wax is a temporary and reversible change on cooling, wax solidifies, and no new product is formed while burning of a candle is a permanent change i.e. products are not convertible, a new substance is formed having different composition & different properties.
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संबंधित प्रश्न
Changes in which only ______ properties of a substance change are called physical changes.
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| Column A | Column B |
| 1. a change which cannot be easily reversed | a. man-made change |
| 2 a change that repeats itself at regular intervals | b. chemical chang |
| 3. a change that is made by humans | c. physical change |
| 4. a change in which the original substance cannot be obtained | d. periodic change |
| 5. a change where no new substance is formed | e. irreversible change |
| f . slow change |
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| List I | List II |
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| 2. Rotting of eggs | B: Chemical change |
| 3. Milk turning sour | |
| 4. Tarnishing of copper | |
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