Question #45065

The electrophilic addition of a reagent \ce{E-Nu} to an alkene \ce{A} in a non-polar solvent at 298 K proceeds via the following mechanism:

Step 1: $\ce{E-Nu} \rightleftharpoons \ce{E+} + \ce{Nu-}$ (Fast pre-equilibrium, equilibrium constant $K_{eq}$) Step 2: $\ce{A} + \ce{E+} \rightleftharpoons \ce{I*}$ (Forward rate constant $k_1$, backward $k_{-1}$) Step 3: $\ce{I*} + \ce{Nu-} \xrightarrow{k_2} \ce{P}$ (Product)

The approach of $\ce{E+}$ induces a $+E$ electromeric effect in the alkene, forming the highly reactive, short-lived polarized intermediate $\ce{I*}$. The concentration of $\ce{Nu-}$ is controlled independently by the addition of a soluble salt containing $\ce{Nu-}$.

Applying the Steady State Approximation (SSA) to $\ce{I*}$, determine the overall rate law for the formation of product $\ce{P}$. Furthermore, identify the apparent order of the reaction with respect to $[\ce{Nu-}]$ under Condition I ($k_{-1} \gg k_2[\ce{Nu-}]$) and Condition II ($k_2[\ce{Nu-}] \gg k_{-1}$), respectively.