Chapter 5.8, Problem 11P

Interpretation Introduction

Interpretation:

A chemical equation using the curved arrows for the rate-determining step of the given reaction which follows ${\text{S}}_{\text{N}}\text{1}$ mechanism is to be written.

Concept introduction:

In ${\text{S}}_{\text{N}}\text{1}$ reaction, the rate determining step is the formation of carbocation.

The slow step in the mechanism is the rate determining step.

The ${\text{S}}_{\text{N}}\text{1}$ reaction means unimolecular nucleophilic substitution reaction that means rate determining step involves only one reactant.

The reaction of secondary or tertiary alcohol with hydrogen bromide proceeds through ${\text{S}}_{\text{N}}\text{1}$ mechanism.

${\text{S}}_{\text{N}}\text{1}$ mechanism proceeds through three elementary steps.

The first step is the formation of oxonium ion which is the fast step, second step is formation of carbocation which is a slow step, hence, the rate determining step and third step is the attack of halide ion on carbocation to give the corresponding alkyl halide.