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Indian Forest Service (Mains)

Chemistry optional

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

Paper I covers physical and inorganic chemistry.

Indian Forest Service (Mains), Chemistry optional · 2024 · Paper I

Q8(b). Critical compressibility of a van der Waals gas

Question

Using critical constants Pc, Vc, Tc for a real gas satisfying the van der Waals equation, find the critical compression factor near the critical point.

Answer in brief

The van der Waals prediction is Zc = PcVm,c/(RTc) = 3/8 = 0.375.

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Topic notes: real gases, the van der Waals equation, critical constants and Boyle temperature, with every Civil Services, IFoS and Geo-Scientist PYQ →

Coversvan der Waals equationcritical constantscritical compressibility factorZc = 3/8real gases

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