The product of the following reaction is:

In the chemical reaction $CH_3CH_2NH_2 + CHCl_3 + 3KOH \rightarrow (a) + (b) + 3H_2O$,what are the products $(a)$ and $(b)$ respectively?

During the acetylation of amines,what is replaced by acetyl groups?

The preferred sites of protonation in the following compounds are:
$(i)$ $CH_3CONHCH_3$
(ii) $2$-aminopyridine

$Methylamine$ on treatment with $chloroform$ $(CHCl_3)$ and ethanolic caustic alkali $(KOH)$ gives a foul-smelling compound. The compound is:

$A$ hydrocarbon $A$ $(C_{4}H_{8})$ on reaction with $HCl$ gives a compound $B$ $(C_{4}H_{9}Cl)$ which on reaction with $1 \ mol$ of $NH_{3}$ gives compound $C$ $(C_{4}H_{11}N)$. On reacting with $NaNO_{2}$ and $HCl$ followed by treatment with water,compound $C$ yields an optically active compound $D$. The compound $D$ is