The chemical reaction shown in the image represents the reduction of a diazonium salt to an aromatic hydrocarbon. Identify the reagent typically used for this transformation.

An amine $(X)$ reacts with $p-$toluene sulphonyl chloride to give the product,$Y$,which is insoluble in alkali. The product of $X$ with benzoyl chloride is

Which of the following reactions is an example of ammonolysis?

The correct order of the basic strength of methyl substituted amines in aqueous solution is

$A$ student has been given a compound $x$ of molecular formula $C_6H_7N$. $x$ is sparingly soluble in water. However, on addition of dilute mineral acid, $x$ becomes soluble in water. $x$ when treated with $CHCl_3$ and $KOH$ (alc.) produces $y$. $y$ has a specific unpleasant smell. On treatment with benzenesulphonyl chloride, $x$ gives a compound $z$ which is soluble in alkali. The number of different $H$ atoms present in $z$ is:

What are the structures of $X$,$Y$ and $Z$ in the following reaction sequence?