Write the reaction of conversion of amine into nitro compounds.

Scheme $1$ and $2$ describe the conversion of $\mathrm{P}$ to $\mathrm{Q}$ and $\mathrm{R}$ to $\mathrm{S},$ respectively. Scheme $3$ describes the synthesis of $\mathrm{T}$ from $\mathrm{Q}$ and $\mathrm{S}.$ The total number of $\mathrm{B}\mathrm{r}$ atoms in a molecule of $\mathrm{T}$ is

Scheme $1$:



Scheme $2$:



Scheme$3$:

The nitrogen cycle is given below. Identify A and B in it.

Study the following illustration of nitrogen cycle and identify $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ in it.

Aniline reacts with mixed acid (conc. ${\mathrm{HNO}}_3$ and conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$ ) at $288\mathrm{ }\mathrm{K} \text{to give} \mathrm{P}\mathrm{ }(51 \%),\mathrm{ }\mathrm{Q}\mathrm{ }\left(47\mathrm{\%}\right) \text{and} \mathrm{R}\mathrm{ }\left(2\mathrm{\%}\right)$ . The major product(s) of the following reaction sequence is (are)

Consider the reaction sequence from $\mathrm{P}$ to $\mathrm{Q}$ shown below. The overall yield of the major product $\mathrm{Q}$ from $\mathrm{P}$ is $75\%.$ What is the amount in grams of $\mathrm{Q}$ obtained from $9.3 \mathrm{mL}$ $\mathrm{P}$? (Use density of $\mathrm{P}$ $=1.00{\text{\hspace{0.33em}g\hspace{0.33em}mL}}^{-1};$ Molar mass of $\mathrm{C}=12.0,\mathrm{H}=1.0,\mathrm{O}=16.0$ and $\mathrm{N}=14.0 \mathrm{g} {\mathrm{mol}}^{-1}$)

Which of the following chemicals are used to manufacture methyl isocyanate that caused "Bhopal Tragedy"?

$\left(\mathrm{i}\right)$ Methylamine.
$\left(\mathrm{ii}\right)$ Phosgene.
$\left(\mathrm{iii}\right)$ Phosphine.
$\left(\mathrm{iv}\right)$ Dimethylamine.

Main processes involved in nitrogen cycle are

Represent the union of two sets by Venn diagram for each of the following.

$X=\{x | x$ is a prime number between $80$ and $100\}$

$Y=\{y | y$ is an odd number between $90$ and $100\}$