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UPSC Combined Geo-Scientist

Chemist

  • 3 descriptive papers
  • 200 marks each
  • 3 h per paper

Mains Paper II covers physical chemistry.

UPSC Combined Geo-Scientist, Mains · 2018 · Mains Paper II

Q4. Entropy of equal-volume gas mixing

Question

3.0 mol H₂ and 1.0 mol N₂ occupy two compartments of equal volume and temperature. The partition is removed and ideal gases mix freely. Find the entropy change.

Answer in brief

ΔS=4Rln 2=23.05 J K⁻¹.

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CoversEntropy of equal-volume gas mixingThermodynamics