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MHT CET202613 April 2026Morning ShiftChemistryThermodynamics (C)Actual

For a certain reaction H = -50 kJ and S = -100 J/K find the temperature so that the reaction is spontaneous.

Options

  1. A650 K
  2. B600 K
  3. C550 K
  4. D450 K

Correct answer

D. 450 K

Step-by-step solution

For a reaction to be spontaneous, the change in Gibbs free energy must be negative, i.e., G Using the Gibbs free energy equation: G = H - T S Substituting the given values ( H = -50000 J and S = -100 J/K): -50000 - T(-100) -50000 + 100T 100T T The reaction is spontaneous at temperatures below 500 K. Among the given options, only 450 K satisfies this condition. Answer: 450 K

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