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JEE Main202429 Jan 2024Morning ShiftChemistryThermodynamics (C)Actual

Which of the following is not correct?

Options

  1. AΔG is negative for a spontaneous reaction
  2. BΔG is positive for a spontaneous reaction
  3. CΔG is zero for a reversible reaction
  4. DΔG is positive for a non-spontaneous reaction

Correct answer

B. ΔG is positive for a spontaneous reaction

Step-by-step solution

∆ G can be expressed as: ∆ G = ∆ H - T ∆ S where ∆ G is the change in free energy ∆ H is the change in enthalpy T is the temperature ∆ S is the change in entropy. Conditions for spontaneous and non spontaneous reactions in terms of free energy change are as follows, ΔG >0 for non-sponateneous reaction ΔG < 0 for spontaneous reaction. ΔG = 0 for equilibrium reaction ( ΔG ) P , T = ( + ) ve for non-spontaneous process Hence option B is the answer.

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