Q7(c). Rate expression for a bimolecular surface reaction
Derive a rate expression for a bimolecular surface reaction A + B → Product. Discuss the kinetics of such a reaction when the gaseous reactants A and B are adsorbed in the following ways: (i) A and B are sparsely adsorbed; (ii) A is relatively more strongly adsorbed than B.
Answer in brief
Rate = kθAθB = kKAKBpApB/(1 + KApA + KBpB)²; (i) rate = kKAKBpApB (second order); (ii) rate = kKBpB/KApA (A inhibits).
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CoversLangmuir–Hinshelwood mechanismsurface reactionheterogeneous catalysisLangmuir adsorption isothermcatalyst poisoning
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