In the above reaction,identify the major product $(A)$ of the reaction.

The product $(X)$ of the reaction is:

In the following sequence of reactions,a compound $A$ (molecular formula $C_{6}H_{12}O_{2}$) with a straight chain structure gives a $C_{4}$ carboxylic acid. $A$ is :
$A$ $\xrightarrow{LiAlH_{4} / H_{3}O^{+}} B$ $\xrightarrow{\text{Oxidation}} C_{4} \text{ carboxylic acid}$

Hydrolysis of an ester gives a carboxylic acid which on Kolbe's electrolysis yields ethane. The ester is

The major products $Q$ and $R$ from the following reactions,respectively are:

Give simple chemical tests to distinguish between the following pairs of compounds.
$(i)$ Propanal and Propanone
$(ii)$ Acetophenone and Benzophenone
$(iii)$ Phenol and Benzoic acid
$(iv)$ Benzoic acid and Ethyl benzoate
$(v)$ Pentan$-2-$one and Pentan$-3-$one
$(vi)$ Benzaldehyde and Acetophenone
$(vii)$ Ethanal and Propanal