When benzyl alcohol is reacted with concentrated $\mathrm{HBr},$ produces the product  $\mathrm{P}$ . The product  $\mathrm{P}$ on reaction with $\mathrm{KCN},$ gives $\mathrm{Q}$ The product $\mathrm{Q}$ on heating with ${\mathrm{H}}_3{\mathrm{O}}^{+}$ generates $\mathrm{R}.$ The molecular formula of $\mathrm{R}$ is:

The major products, $\mathrm{P}$ and $\mathrm{Q}$, formed in the reactions given below are:

The major products $\mathrm{A}$ and $\mathrm{B}$ in the following reaction sequences are

The major product formed in the following reactions

Identify the relation among the rates of following nucleophilic substitution reactions?

The correct statement about the following chemical reaction is

In the following sequence of reactions, the gaseous species $\mathrm{A}\text{,} \mathrm{B}\text{,} \mathrm{D}\text{,} \mathrm{E}$, respectively, are