NEET 2016 Question Paper - Phase-II Code XX Mock Test

A given nitrogen-containing aromatic compound $\text{A}$ reacts with $\text{Sn/HCl}$, followed by ${\text{HNO}}_2$ to give an unstable compound $\text{B}$. $\text{B}$, on treatment with phenol, forms a beautiful coloured compound $\text{C}$ with the molecular formula ${\text{C}}_{12}{\text{H}}_{10}{\text{N}}_2\text{O}$. The structure of compound $\text{A}$ is:

Consider the reaction:
$${\text{CH}}_3{\text{CH}}_2{\text{CH}}_2\text{Br}+\text{NaCN}\to {\text{CH}}_3{\text{CH}}_2{\text{CH}}_2\text{CN}+\text{NaBr}$$
This reaction will be the fastest in:

The correct structure of the product $\text{A}$ formed in the reaction:$\underset{\text{Pd/carbon, ethanol}}{\overset{{\text{H}}_2\text{ (gas, 1 atmosphere)}}{\to }}\text{A}$ is:

Which among the given molecules can exhibit tautomerism?

The correct order of strengths of the carboxylic acids: