During physical adsorption, the variance between the heat of adsorption and the heat of standard condensation is_________________?
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Answer: B. Equal to the heat of wetting
Explanation
Net heat of adsorption in physical processes equals total adsorption heat minus condensation heat. This energy difference corresponds directly to the heat of wetting for the solid surface. Physical adsorption involves weak van der Waals forces similar to vapor condensation. Physical adsorption is fully reversible and characterized by low adsorption enthalpies. Heat of wetting measures thermal energy released when a solid contacts a liquid. Adsorption thermodynamics helps engineers calculate cooling and thermal management requirements.
Adsorption beds in gas purification systems experience temperature swings during operational cycles. Accounting for heat of wetting is crucial in designing adsorption dehumidification equipment. Thermal regeneration of spent adsorbents relies heavily on accurate thermodynamic data. Option A applies to chemisorption where strong surface chemical bonds are actively formed. Option C is incorrect because the heat difference is non-zero in physical adsorption systems. Option D describes total heat released rather than the differential heat of wetting.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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