The reaction of benzene with chlorine in the presence of $Fe$ produces.........

Conversion of benzene diazonium chloride to chlorobenzene is an example of which of the following reactions?

Toluene is nitrated and the resulting product is reduced with tin and hydrochloric acid. The product so obtained is diazotised and then heated with cuprous bromide. The reaction mixture so formed contains

The compound from which chlorobenzene cannot be prepared easily is

Which of the following reactions uses a diazonium salt as a reactant?

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