Identify the product $A$ in the following reaction:
Aniline $\xrightarrow{(CH_3CO)_2O / \text{pyridine}} A$

Nitration of aniline also gives $m$-nitroaniline in a strong acidic medium because:

Reaction of $R-CONH_2$ with a mixture of $Br_2$ and $KOH$ gives $R-NH_2$ as the main product. The intermediates involved in this reaction are :-
$(A)$ $R-CONHBr$
$(B)$ $R-NH-Br$
$(C)$ $R-N=C=O$
$(D)$ $R-CONBr_2$

$A$ compound with molecular mass $180$ is acylated with $CH_3COCl$ to get a compound with molecular mass $390$. The number of amino groups present per molecule of the former compound is:

The product of the mustard oil reaction is:

Identify the products $y$ and $x$ in the following reaction sequence:
$C_6H_5CONH_2 \xrightarrow{NaOBr} y$
$C_6H_5CONH_2 \xrightarrow[(ii) H_3O^+]{(i) C_6H_5SO_2Cl / py, \Delta} x$