Concept:The experimental order of a reaction with respect to a specific reactant becomes the mathematical exponent for that reactant's concentration in the rate law.
Solution:- The problem explicitly states the reaction is "first order with respect to A". This means the concentration of A, \( [\text{A}] \), must have an exponent of 1.
- It states it is "second order with respect to B". This means the concentration of B, \( [\text{B}] \), must have an exponent of 2.
- Combining these into the standard rate equation format yields: Rate = \( k[\text{A}]^1[\text{B}]^2 \).
Why other options are incorrect:Option B represents a reaction that is first order for both A and B. Option C represents a reaction that is second order for A and first order for B (the inverse of the question).
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