The rate law for a reaction is found to be Rate = k[A]²[B].Which of the following mechanisms gives this rate law? I.A + B E (fast) E + B $\to$ C + D (slow) II.A + B E (fast) E + A $\to$ C + D (slow) III.A + A $\to$ E (slow). E + B $\to$ C + D (fast)

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The rate law given is Rate = k[A]^^{^2}[B]. The only mechanism that involves [A]^S1 and [B] is mechanism II. In mechanism II, the first step is fast and involves [A] and [B]. Therefore, the rate-determining step is the second step which is slow and involves [E], [C], and [D]. The rate law derived from this mechanism would be Rate = k'[E][C][D]. However, if we substitute [E] with the concentration of the intermediate [A], we get Rate = k[A]^^{^2}[B]. Thus, mechanism II gives the desired rate law.

The Rate Law for a Reaction Is Found to Be →\to→

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