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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.
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
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Tick the most appropriate answer.
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- change in shape.
- change in size.
- change in molecular composition.
- none of these
Tick the most appropriate answer.
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Classify the following as a physical or a chemical change.
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