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JEE Main202126 Aug 2021Morning ShiftChemistrySurface ChemistryActual

Which one of the following is correct for the adsorption of a gas at a given temperature on a solid surface?

Options

  1. AΔH > 0 , ΔS > 0
  2. BΔH < 0 , ΔS > 0
  3. CΔH > 0 , ΔS < 0
  4. DΔH < 0 , ΔS < 0

Correct answer

D. ΔH < 0 , ΔS < 0

Step-by-step solution

Adsorption is spontaneous process therefore change in free energy is negative. Adsorption of gas on solid surface is exothermic process & entropy is decrease in this process so ΔH < 0 , ΔS < 0

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