Question

Which of the following phrases are not correctly associated with $S{{N}_{1}}$reaction?
1. Rearrangement is possible
2. Rate is affected by polarity of solvent
3. The strength of the nucleophile is important in determining rate
4. The reactivity series is tertiary>secondary>primary
5. Proceeds with complete inversion of configuration
A. $3,5$
B. $5only$
C. $2,3,5$
D. $3only$

Answer 1

We know that $S{{N}_{1}}$ reaction is defined as the nucleophilic substitution reaction in which to determine the rate of the reaction is unimolecular. It is one of the types of organic substitution reactions. The rate equation for $S{{N}_{1}}$ is defined as that the $S{{N}_{1}}$ reaction is depended on the electrophile but not on nucleophile.

Complete step by step solution:
The reaction is a two-step reaction that involves the substitution of a nucleophile in the presence of a polar solution. This reaction depends on the concentration of substrate that is being used. On increasing the concentration of substrate, the rate of the reaction also increases. The reaction does not depend on the concentration of the nucleophile. The inversion of configuration is found only $5$ of the compounds which is also not complete.
In the $S{{N}_{1}}$ reaction the polarity of solvents affects the rate and the reactivity decreases in the order of $tertiary>secondary>primary.$ There is the presence of configuration retention in the reaction.
The first possibility is if the reaction occurs by the attachment of the nucleophile at the same site as that of the previous nucleophile. This leads to the formation of a product that has identical geometry as that of the reactant but contains a different functional group.

So, the correct answer is Option A

Note: Note that the haloalkanes have the tendency to be converted into alcohols by using the hydroxide ion through the aqueous medium by $S{{N}_{1}}$reactions. The conditions for substitution reactions are that the temperature should be low and the solution should be in aqueous state. During the $S{{N}_{1}}$ one concentration affects the reaction instead of two that is the substrate affect the reaction.