When a primary amine reacts with chloroform in ethanolic $KOH$,the product formed is:

What is the nature of an aqueous solution of methylamine?

The major product $(R)$ of the following reaction is:
$C_6H_5NH_2$ $\xrightarrow[{0 \, ^\circ C}]{{HNO_2}} P$ $\xrightarrow{{HBF_4}} Q$ $\xrightarrow[{Cu, \, \Delta }]{{NaNO_2}} R$

When primary amine is heated with $CS_2$ in presence of excess mercuric chloride,it gives isothiocyanate. This reaction is called

In the given reaction $A$ is :- $A$ $\xrightarrow{\text{Reduction}} B$ $\xrightarrow{HNO_2} C_2H_5OH$

Among the following,which one does not act as an intermediate in the Hofmann rearrangement?