Match the compounds in Column I with their characteristic test(s)/reactions(s) given in Column II. Indicate…
Match the compounds in Column I with their characteristic test(s)/reactions(s) given in Column II. Indicate your answer by darkening the appropriate bubbles of the $4 \times 4$ matrix given in the ORS.
(A) r,s, (B) p,q, (C) p,q,r, (D) p
(A) r, (B) p,q,s, (C) p,q,s, (D) p,q
(A) s, (B) q,r,s, (C) p,q,r,s, (D) p,q
(A) r,s, (B) p,q,s, (C) p,q,r, (D) p
Solution
A-r; B-p, q; C- p, q, r; D-p
Sodium fusion extract gives Prussian blue when nitrogen is present alongwith carbon. Phenolic group and carboxylate gives positive $\mathrm{FeCl}_3$ test - white precipitate comes with $\mathrm{AgCl}$.
$
\text { Hydrazone formation occurs effectively at } \mathrm{pH} \approx 4.5 \text {. The reaction proceeds in that }
$
condition only when $\mathrm{H}^{+}$concentration is merely sufficient to activate. As $\mathrm{H}^{+}$concentration raises, sufficient molecule of hydrazone gets converted into hydrazonium which is not nucleophilic and reaction becomes impossible. Further, low concentration of $\mathrm{H}^{+}$(in the case of hydrolysis of 2, 4-dinitrophenyl hydrazonium bromide) is not effective to proceed elimination (rate determining step).
If it is assumed that the given hydrazonian bromiate is the result as salt main $\mathrm{HBr}$ is used as acid catalyst. Remember! hydrazone formation involves first addition and then elimination (res). In the second step substitution dominates over elimination ( $\mathrm{HBr}$ is not a dehydrating reagent mutually)
