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JEE Main202131 Aug 2021Evening ShiftChemistryThermodynamics (C)Actual

The incorrect expression among the following is :

Options

  1. AFor isothermal process w reversible  = - nRT   ln V f   V i
  2. BlnK = ΔH ° - TΔS ° RT
  3. CΔG System  ΔS Total  = - T (at constant P)
  4. DK = e - ΔG ° / RT

Correct answer

B. lnK = ΔH ° - TΔS ° RT

Step-by-step solution

ΔG = ΔG ° + RT   lnQ at equilibrium Q = K eq and ΔG = 0 ΔG ° = - RT   lnK eq and ΔG ° = ΔH ° - TΔS ° ΔH ° - TΔS ° = - RTlnK eq So, lnKeq = - ΔH ° - TΔS ° RT = - ΔH ° + TΔS ° RT

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