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MHT CET202523 Apr 2025Evening ShiftChemistryThermodynamics (C)Actual

Identify from following the correct set of thermodynamic conditions for the reaction to be spontaneous below equilibrium temperature.

Options

  1. AH < 0 and S < 0
  2. BH>0 and S>0
  3. CH 0
  4. DH >0 and S < 0

Correct answer

A. H < 0 and S < 0

Step-by-step solution

The spontaneity of a reaction is determined by the Gibbs free energy: G = H - T S , with G For H T| S| , equivalent to T Other combinations yield different behavior: H > 0 , S > 0 gives spontaneity above T_ eq ; H 0 is always spontaneous; H > 0 , S The conditions H A .

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