A slab of ice at 273K and at atmospheric pressure melts.(a) What is the nature of work done on the ice- water system by the atmosphere? (b)What happens to the internal energy of ice water- system?

 A) The vol. of ice decreases on melting. Hence, the work done by the atmosphere on ice-water system is +ve in nature.

B) Heat is absorbed by ice during melting the internal energy of the ice water system increases.

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