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प्रश्न
Give a reason why
Freezing of water is a reversible change while burning of a candle – an irreversible change.
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उत्तर
Freezing of water is reversible change as on heating frozen ice changes to water by heating.
Burning of a candle is irreversible change as on reversing the conditions we can not get candle back out of CO2, water vapours and wax vapours.
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