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JEE Main202228 Jul 2022Morning ShiftChemistryThermodynamics (C)Actual

Which of the following relation is not correct?

Options

  1. AΔH = ΔU - PΔV
  2. BΔU = q + W
  3. CΔS sys + ΔS surr ≥ 0
  4. DΔG = ΔH - TΔS

Correct answer

A. ΔH = ΔU - PΔV

Step-by-step solution

Enthalpy, in a thermodynamic system, is the measure of its energy which is equal to the sum of the internal energy and the product of its pressure and volume. H   =   U + PV (By definition) ΔH = ΔU + Δ PV or   ΔH = ΔU + VΔP +   PΔV at constant pressure ΔH = ΔU + PΔV So, option A is incorrect. ΔU = q + W First law of thermodynamics. ΔS sys + ΔS surr ≥ 0   or   ΔS Universe   ≥ 0 A form of second law of

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