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AP EAMCET202021 Sep 2020Morning ShiftChemistryThermodynamics (C)Actual

If, ( H>0 ) and ( S>0 ), the reaction can proceed spontaneously at

Options

  1. Alow temperature
  2. Bhigh temperature
  3. Call temperature
  4. Dwill never be spontaneous

Correct answer

B. high temperature

Step-by-step solution

When both ( H ) and ( S ) are positive then the process will be an endothermic which involves an increase in system entropy. In this case, ( G ) will be negative, if the magnitude of the (T S ) term is greater than ( H ). If the (T S ) term is less than ( H ), the free energy change will be positive. Such a process is spontaneous at high temperatures and non-spontaneous at low temperatures. Hence, the correct option is (b).

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