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AP EAMCET20227 Jul 2022Morning ShiftChemistryThermodynamics (C)Actual

Which of the following conditions are not suitable for a spontaneous reaction?

Options

  1. AH 0 at low temperature.
  2. BH < 0 and S < 0 at high temperature.
  3. CH < 0 and S < 0 at low temperature.
  4. DH>0 and S>0 at high temperature.

Correct answer

B. H < 0 and S < 0 at high temperature.

Step-by-step solution

G (Gibbs' free energy) must be negative for a spontaneous reaction. Using Gibbs' free energy equation, we can find favourable conditions. G= H-T S [ array l H= Change in enthalpy S= Change in entropy T= Temperature array ]

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