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Question 31074
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Kinetic Theory and Thermodynamics: Thermodynamics MCQ

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ThermodynamicsHardQuestion 31074

Question

Helmholtz free energy F = U − TS. For a spontaneous isothermal process, ΔF:
  1. A
    Increases
  2. B
    Is zero
  3. C
    Decreases or stays zero
    Correct
  4. D
    Is always positive

Correct answer

Decreases or stays zero

Explanation

At constant T and V, equilibrium corresponds to minimum F. Spontaneous processes decrease F; equilibrium means ΔF = 0.

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