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JEE Main202524 Jan 2025Morning ShiftChemistryThermodynamics (C)Actual

Let us consider an endothermic reaction which is non-spontaneous at the freezing point of water. However, the reaction is spontaneous at boiling point of water. Choose the correct option.

Options

  1. ABoth H and S are (-ve)
  2. BH is (-ve) but S is (+ve)
  3. CH is (+ ve ) but S is (- ve )
  4. DBoth H and S are (+ve)

Correct answer

D. Both H and S are (+ve)

Step-by-step solution

On increasing temperature, the given endothermic reaction becomes spontaneous. G= H-T S For spontaneity, G 0 So, S should be +ve.

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