$R$ is

Identify the major product formed from the following reaction sequence.

$C_{6}H_{5}NO_{2}$ $\xrightarrow{Sn+HCl} A$ $\xrightarrow{C_{6}H_{5}N_{2}^{\oplus}Cl^{\ominus}} P$
(Yellow coloured compound)
Consider the above reaction,the Product "$P$" is:

In the chemical reaction $CH_3CH_2NH_2 + CHCl_3 + 3KOH \rightarrow (a) + (b) + 3H_2O$,what are the products $(a)$ and $(b)$ respectively?

In the reaction $CH_3Br + KCN_{(alc)} \to X \xrightarrow[Na + C_2H_5OH]{reduction} Y$,identify $Y$.

Nitration of aniline also gives $m$-nitroaniline in a strong acidic medium because: