COMEDK 2025 Morning Solved Paper

Concept:Glucose undergoes distinct reactions depending on the reagent and conditions, leading to different oxidation or reduction products.Explanation:A. Glucose with $\mathrm{HI}$ (heat) causes complete reduction to $n$‑hexane, which is $\mathrm{CH}_3-(\mathrm{CH}_2)_4-\mathrm{CH}_3$ (Q).B. Glucose with $\mathrm{Br}_2(\text{aq})$ results in mild oxidation of the aldehyde group to a carboxylic acid, forming gluconic acid $\mathrm{HOOC}-(\mathrm{CHOH})_4-\mathrm{CH}_2\mathrm{OH}$ (S).C. Glucose with conc. $\mathrm{HNO}_3$ leads to strong oxidation at both ends, producing glucaric acid $\mathrm{HOOC}-(\mathrm{CHOH})_4-\mathrm{COOH}$ (P).D. Glucose with Tollens’ reagent $(2\,[\mathrm{Ag}(\mathrm{NH}_3)_2]\mathrm{OH})$ gives mild oxidation in ammonia, forming the ammonium salt of gluconic acid $\mathrm{NH}_4\mathrm{OOC}-(\mathrm{CHOH})_4-\mathrm{CH}_2\mathrm{OH}$ (R).Thus the correct matches are A → Q, B → S, C → P, D → R.Answer:Option D: $\mathrm{A}=\mathrm{Q}$, $\mathrm{B}=\mathrm{S}$, $\mathrm{C}=\mathrm{P}$, $\mathrm{D}=\mathrm{R}$.