Methods used for purification of organic compounds are based on :

Compare the energies of following sets of quantum numbers for multielectron system.

(A) $$\mathrm{n}=4,1=1$$

(B) $$\mathrm{n}=4,1=2$$

(C) $$\mathrm{n}=3, \mathrm{l}=1$$

(D) $$\mathrm{n}=3,1=2$$

(E) $$\mathrm{n}=4,1=0$$

Choose the correct answer from the options given below :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : $$\mathrm{S}_{\mathrm{N}} 2$$ reaction of $$\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{Br}$$ occurs more readily than the $$\mathrm{S}_{\mathrm{N}} 2$$ reaction of $$\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{Br}$$.

Reason (R) : The partially bonded unhybridized p-orbital that develops in the trigonal bipyramidal transition state is stabilized by conjugation with the phenyl ring.

In the light of the above statements, choose the most appropriate answer from the options given below :

On reaction of Lead Sulphide with dilute nitric acid which of the following is not formed?