The product $(A)$ of the given reaction is:

In the above conversion,the correct sequence of reagents to be added is:

Amine compounds exhibit ............ isomerism.

$A$ is a neutral organic compound $(M.F.: C_8H_9ON)$. On treatment with aqueous $Br_2 / HO^{(-)}$, $A$ forms a compound $B$ which is soluble in dilute acid. $B$ on treatment with aqueous $NaNO_2 / HCl$ $(0-5^{\circ}C)$ produces a compound $C$ which on treatment with $CuCN / NaCN$ produces $D$. Hydrolysis of $D$ produces $E$ which is also obtainable from the hydrolysis of $A$. $E$ on treatment with acidified $KMnO_4$ produces $F$. $F$ contains two different types of hydrogen atoms. The structure of $A$ is

Write the chemical reactions for the following conversions:
$1.$ Aniline to Picric acid
$2.$ Ethanal to Butan$-2-$ol

$A$ given nitrogen-containing aromatic compound $A$ reacts with $Sn/HCl,$ followed by $HNO_2$ to give an unstable compound $B$. $B,$ on treatment with phenol,forms a beautiful coloured compound $C$ with the molecular formula $C_{12}H_{10}N_2O.$ The structure of compound $A$ is