Question

Which of the following statements is correct regarding unimolecular nucleophilic substitution reactions?

(a) It takes place in three steps.

(b) The rate of the reaction depends on the concentration of all the reactants.

(c) The first step is the slowest and determines the rate of reaction.

(d) None of the steps are reversible.

The question was posed to me during an interview.

Origin of the question is Haloalkanes & Haloarenes in section Haloalkanes and Haloarenes of Chemistry – Class 12

Answer 1

Right choice is (c) The first step is the slowest and determines the rate of reaction.

Explanation: SN1 reactions follow first order kinetics and take place in two steps, of which the first one is the slowest, rate determining and reversible step.