The chlorobenzene is generally obtained from a corresponding diazonium salt by reacting it with

The raw material for the Raschig process is

In Gattermann reaction,a diazonium group is replaced by $\underline{X}$ using $\underline{Y}$. $\underline{X}$ and $\underline{Y}$ are:
$\underline{X} \quad \underline{Y}$

In this process,the product $A$ is:

The compound from which chlorobenzene cannot be prepared easily is

Which of the following are intermediates in the Sandmeyer reaction?
$(i)$ $C_6H_5N^{+} \equiv NCl^{-}$
$(ii)$ $C_6H_5N^{+} \equiv N$
$(iii)$ $\overset{\centerdot }{C}_6H_5$
$(iv)$ $C_6H_5Cl$