The reagent which can be used to distinguish between the products of acid hydrolysis of the two compounds $\mathrm{A}$ and $\mathrm{B}$ given above is

The reagent $\mathrm{A}$ which can be used for the above conversion is

Which of the following will undergo base catalysed condensation reaction with cyclopentadiene to form this compound?

In the above reaction sequence, the product $\mathrm{C}$ is

Predict the compound $\mathrm{C}$ in the following series of reactions.

${\mathrm{CH}}_3\mathrm{COOH}\stackrel{{\mathrm{PCl}}_5}{\to }\left[\mathrm{A}\right]\underset{\mathrm{Anhydrous} {\mathrm{AlCl}}_3}{\overset{{\mathrm{C}}_6{\mathrm{H}}_6}{\to }}\left[\mathrm{B}\right]\stackrel{{\mathrm{CH}}_3\mathrm{MgBr}}{\to }\left[\mathrm{C}\right]$

Identify $\mathrm{B}$ in the above reaction.

The alkyl group $\mathrm{R}$ of the reagent will be