Which reagent is used in the conversion of $C_2H_5NH_2$ to $C_2H_5Cl$?

Assertion: Only a small amount of $HCl$ is required in the reduction of nitro compounds with iron scrap.
Reason: $FeCl_2$ formed gets hydrolysed to release $HCl$ during the reaction.

The reaction of $N$-phenylbenzamide with $NO_2^{\oplus}$ (nitronium ion) yields which product?

The reaction of benzylamine with nitrous acid $(HNO_2)$ produces product $A$. Identify product $A$.

Which among the following is a correct order of $pK_b$ values of amines in the aqueous phase?

Alkylamine dissolves in hydrochloric acid to form alkylammonium chloride. The nitrogen in the latter salt is: