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Question 31056
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Kinetic Theory and Thermodynamics: Entropy MCQ

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EntropyHardQuestion 31056

Question

For mixing of two ideal gases at same T and P, entropy change is:
  1. A
    Zero (no T change)
  2. B
    Positive (entropy of mixing)
    Correct
  3. C
    Negative (ordering increases)
  4. D
    Depends on molar masses

Correct answer

Positive (entropy of mixing)

Explanation

Mixing increases disorder → entropy of mixing ΔS_mix = −nR(x₁lnx₁ + x₂lnx₂) > 0 where x₁, x₂ are mole fractions.

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