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NEETChemistryThermodynamics (C)

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): For an irreversible isothermal expansion of an ideal gas, the sum of the entropy change of the system and surroundings is greater than zero. Reason (R): The internal energy of an ideal gas remains constant during an isothermal process. In the light of the above statements, choose the most appropria

Options

  1. ABoth Assertion (A) and Reason (R) are correct but Reason (R) is not the correct explanation of Assertion (A).
  2. BBoth Assertion (A) and Reason (R) are correct and Reason (R) is the correct explanation of Assertion (A).
  3. CAssertion (A) is correct but Reason (R) is not correct.
  4. DAssertion (A) is not correct but Reason (R) is correct.

Correct answer

A. Both Assertion (A) and Reason (R) are correct but Reason (R) is not the correct explanation of Assertion (A).

Step-by-step solution

Assertion (A) is correct: According to the Second Law of Thermodynamics, for any spontaneous or irreversible process, the total entropy of the universe (system + surroundings) must increase. Thus, S_ total = S_ sys + S_ surr > 0 . Reason (R) is correct: For an ideal gas, internal energy is a function of temperature only. In an isothermal process, temperature is constant ( T = 0 ), so the change in internal energy is zero ( U = 0 ). However, Reason (R) is not the correct explanation for Assertion (A). The increase i

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