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Adsorption of gases on solid surface is generally exothermic because

Options

  1. Aenthalpy is positive
  2. Bentropy decreases
  3. Centropy increases
  4. Dfree energy increases

Correct answer

B. entropy decreases

Step-by-step solution

Thermodynamics of adsorption: i. Δ S < 0 because gaseous phase decrease ii. Δ G < 0 because process is spontaneous so Δ G = Δ H - T Δ S - v e = Δ H - + v e - v e Δ H = - v e iii. Δ H < 0 so adsorption is an exothermic process.

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