Question 190: Thermodynamics & KTG

Question

During the melting of a slab of ice at 273 K at atmospheric pressure :

Accepted Answer

During the melting of a slab of ice at 273 K under atmospheric pressure, the following occurs:
As the ice melts, its volume decreases. Because of this volume reduction, the atmosphere exerts a positive work on the ice-water system. When heat is absorbed by the ice-water system, we denote the absorbed heat as $ \Delta \mathrm{Q} $, which is positive. The work done by the ice-water system is negative because it is being compressed by the external pressure.
According to the first law of thermodynamics:
$ \Delta \mathrm{U} = \Delta \mathrm{Q} + \Delta \mathrm{W} $
In this equation, $ \Delta \mathrm{U} $ represents the change in internal energy, $ \Delta \mathrm{Q} $ is the heat absorbed by the system, and $ \Delta \mathrm{W} $ is the work done by the system. Since the work done is negative and the absorbed heat is positive, the overall internal energy ($ \Delta \mathrm{U} $) increases.

Answer

Internal energy of ice-water system remains unchanged.

Answer

Positive work is done by the ice-water system on the atmosphere.

Answer

Positive work is done on the ice-water system by the atmosphere.

Answer

Internal energy of the ice-water system decreases.

Thermodynamics & KTG

During the melting of a slab of ice at 273 K at atmospheric pressure :

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