Identify the correct decreasing order of $pK_b$ values of the following compounds.

Nitrobenzene on reduction with zinc and $NH_4Cl$ gives:

Which of the following possess powerful mustard smell (and are called mustard oils)?

Identify $Z$ in the above sequence of reactions.

$RCONH_2$ is converted into $RNH_2$ by means of Hofmann bromamide degradation. In this reaction,$RCONHBr$ is formed from which this reaction has derived its name. Electron donating group at phenyl activates the reaction. Hofmann degradation reaction is an intramolecular reaction.
$1.$ How can the conversion of $(i)$ to $(ii)$ be brought about?
$(A)$ $KBr$
$(B)$ $KBr + CH_3ONa$
$(C)$ $KBr + KOH$
$(D)$ $Br_2 + KOH$
$2.$ Which is the rate determining step in Hofmann bromamide degradation?
$(A)$ Formation of $(i)$
$(B)$ Formation of $(ii)$
$(C)$ Formation of $(iii)$
$(D)$ Formation of $(iv)$
$3.$ What are the constituent amines formed when the mixture of $(i)$ and $(ii)$ undergoes Hofmann bromamide degradation?
Give the answer for question $1$,$2$,and $3$.

The amine formed from an amide by means of bromine and alkali has