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MHT CET202615 April 2026Evening ShiftChemistryThermodynamics (C)Actual

For a certain reaction, H^0 is -345 kJ and S^0 is -123 JK ⁻¹ . At what temperature the change over from spontaneous to nonspontaneous will occur?

Options

  1. A1052 K
  2. B1956 K
  3. C2568 K
  4. D2805 K

Correct answer

D. 2805 K

Step-by-step solution

The changeover from spontaneous to nonspontaneous occurs when G^0 = 0 . Using the Gibbs free energy equation: G^0 = H^0 - T S^0 Setting G^0 = 0 gives: T = H^0 S^0 Substituting the given values (converting H^0 to Joules): T = -345 10^3 J -123 JK ⁻¹ T = 2804.87 K T 2805 K Answer: 2805 K

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