Question

According to the Entropy hypothesis, which one of the following statements is correct:

• A. Entropy is intensive property and entropy of system is sum of entropy of its parts.
• B. Entropy can be produced, or in the limit of a reversible process be conserved, but entropy can never be destroyed.
• C. Entropy is not transferred with heat, but there is entropy transfer associated with energy transfer as work.
• D. Entropy can not measures the amount of microscopic randomness.

Hint:

Remember the core idea of the Second Law of Thermodynamics: "The entropy of the universe always increases or stays the same." It never decreases. This simple phrase helps you quickly evaluate statements about entropy changes.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The question asks for the correct statement describing the nature of entropy, which is governed by the Second Law of Thermodynamics.
Step 2: Detailed Explanation:
Let's analyze each statement:
(A) "Entropy is intensive property and entropy of system is sum of entropy of its parts." This is incorrect. Entropy is an extensive property, meaning it scales with the size of the system. The total entropy of a system is indeed the sum of the entropy of its parts, which is the definition of an extensive property.
(B) "Entropy can be produced, or in the limit of a reversible process be conserved, but entropy can never be destroyed." This is a correct statement of the Second Law of Thermodynamics. For any real (irreversible) process, the total entropy of an isolated system (or the universe) increases (\(\Delta S>0\)). In the idealized case of a reversible process, the total entropy is conserved (\(\Delta S = 0\)). The law forbids any process in which the total entropy would decrease.
(C) "Entropy is not transferred with heat, but there is entropy transfer associated with energy transfer as work." This is incorrect. Entropy transfer is fundamentally associated with heat transfer (\(dS = \frac{\delta Q_{rev}}{T}\)). There is no entropy transfer associated with work in a reversible process.
(D) "Entropy can not measures the amount of microscopic randomness." This is incorrect. The statistical definition of entropy, \(S = k_B \ln \Omega\), directly relates entropy to \(\Omega\), the number of accessible microstates. Therefore, entropy is precisely the measure of microscopic randomness or disorder.
Step 3: Final Answer:
The only correct statement is (B), which is a qualitative summary of the Second Law of Thermodynamics.