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Which of the following statements pertaining to entropy are correct? 1. The entropy of a system reaches its minimum value when it is in a state of equilibrium with its surroundings 2. Entropy is conserved in all reversible processes 3. Entropy of a substance is least in solid phase 4. Entropy of a solid solution is not zero at absolute zero temperature

Which of the following statements pertaining to entropy are correct? 1. The entropy of a system reaches its minimum value when it is in a state of equilibrium with its surroundings 2. Entropy is conserved in all reversible processes 3. Entropy of a substance is least in solid phase 4. Entropy of a solid solution is not zero at absolute zero temperature Correct Answer 2, 3 and 4 only

Explanation:

  • The entropy in the reversible systems is conserved because there is no entropy generation in the reversible process.
  • The third law of thermodynamics states that the entropy of a perfect crystal is zero at the absolute zero temperature as it represents the maximum degree of order.
  • However, a substance not having a perfect crystalline structure and possessing a degree of randomness such as a solid solution or a glassy solid has a finite value of entropy at absolute zero.
  • Since the disorder of molecules is less in the solid phase than the gaseous or liquid phase, hence the solid phase will have the least entropy.
  • The entropy attains its maximum value when the system reaches a stable equilibrium state from a non-equilibrium state. This is the state of maximum disorder.
  • Entropy change of the universe in all reversible processes is zero.

Related Questions

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