JEE Main 2023ChemistryBiomoleculesCarbohydratesmediumMCQ

JEE Main 2023 — Biomolecules Question with Solution

From: JEE Main 2023 (Online) 30th January Morning Shift

Question

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

Assertion (A) : Ketoses give Seliwanoff's test faster than Aldoses.

Reason (R) : Ketoses undergo -elimination followed by formation of furfural.

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

Choose an option

Show full solutionCorrect option: C
Correct answer
C(A) is true but (R) is false

Step-by-step explanation

Seliwanoff 's test is a differentiating test for Ketose and aldose. This test relies on the principle that the keto hexose are more rapidly dehydrated to form 5-hydroxy methyl furfural when heated in acidic medium which on condensation with resorcinol, Cherry red or brown red coloured complex is formed rapidly indicating a positive test.

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About this question

This is a previous-year question from JEE Main 2023, covering the Biomolecules chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.