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JEE Main201911 Jan 2019Evening ShiftChemistryThermodynamics (C)Actual

The standard reaction Gibbs energy for a chemical reaction at an absolute temperature T is given by G ^ = A - BT where A and B are non-zero constants. Which of the following is true about this reaction?

Options

  1. AExothermic if B < 0
  2. BEndothermic if A >0
  3. CEndothermic if A 0
  4. DExothermic if A >0 and B < 0

Correct answer

B. Endothermic if A >0

Step-by-step solution

G^ =A-B T A and B are non-zero constants G^ = H^ -T S^ =A-B T Reaction will be endothermic if G ^ >0 . Hence, A >0 and B < 0

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