A trinitro compound, 1,3,5-tris-(4-nitrophenyl)benzene, on complete reaction with an excess of $\mat

Question

A trinitro compound, 1,3,5-tris-(4-nitrophenyl)benzene, on complete reaction with an excess of $\mathrm{Sn} / \mathrm{HCl}$ gives a major product, which on treatment with an excess of $\mathrm{NaNO}_{2} / \mathrm{HCl}$ at $0^{\circ} \mathrm{C}$ provides $P$ as the product. $P$, upon treatment with\ excess of $\mathrm{H}_{2} \mathrm{O}$ at room temperature, gives the product $Q$. Bromination of $Q$ in aqueo us medium furnishes the product $R$. The compound $P$ upon treatment with an excess of phenol under basic conditions gives the product $S$.\ The molar mass difference between compounds $Q$ and $R$ is $474 \mathrm{~g} \mathrm{~mol}^{-1}$ and between compounds $P$ and $S$ is $172.5 \mathrm{~g} \mathrm{~mol}^{-1}$.\The total number of carbon atoms and heteroatoms present in one molecule of $S$ is $\_\_\_\_$ .\ [Use: Molar mass (in $\mathrm{g} \mathrm{mol}^{-1}$ ): $\mathrm{H}=1, \mathrm{C}=12$, $\mathrm{N}=14, \mathrm{O}=16, \mathrm{Br}=80, \mathrm{Cl}=35.5$. Atoms other than C and H are considered as heteroatoms]

Professor PC Thomas Classes · Answer

(51.00): Total number of C atoms is $S=42$
Hetero atoms in $S=9$
$42+9=51$\