Q5(b). Temperature and adsorption; detergent and surface tension
Explain with reasons: (i) Physical adsorption decreases with increase in temperature, but chemisorption increases. (3 marks) (ii) On adding detergent in water, surface tension decreases. (2 marks)
Answer in brief
(i) Physisorption is exothermic with no activation energy, while chemisorption is activated; (ii) detergent collects at the surface and weakens the inward pull on surface water.
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Coversphysisorptionchemisorptionadsorption isobarsurfactantGibbs adsorption equation
All parts of Question 5
- 5(a) Order of a gas decomposition from two rates5 marks
- 5(b) Temperature and adsorption; detergent and surface tension5 marks