In the reaction A + B -> Products if B is taken in excess then it is an example of:
Correct answer: C. Pseudo - unimolecular reaction
- A. Second order reaction
- B. Zero order reaction
- C. Pseudo - unimolecular reaction
- D. First order reaction
Explanation
A pseudo-unimolecular reaction or pseudo first order reaction s a reaction whose rate depends on the concentration of a single reactant, raised to the power of one. The rate equation typically includes a term like [A] or [B]. In the given reaction A + B -> Products, the rate of the reaction is expected to be dependent on the concentration of both A and B. However, if B is taken in excess, its concentration remains relatively constant, and the rate of the reaction becomes primarily dependent on the concentration of A. Therefore, the given reaction can be approximated as a pseudo first-order reaction or pseudo-unimolecular reaction with respect to A when B is taken in excess.
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About Order of Reaction
Reaction order shows how the rate depends on the concentration of each reactant, as expressed in the rate law. Coverage includes zero, first and second-order reactions, integrated rate equations, half-life, units of rate constants and the distinction between overall order and molecularity.
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