JEE Main 2019ChemistryAldehydes and KetonesMediumMCQ

JEE Main 2019 — Aldehydes and Ketones Question with Solution

JEE Main 2019 (09 Apr Shift 2)

Question

In the following reaction
carbonyl compound +MeOH⇌HClacetal

Rate of the reaction is the highest for:

Choose an option

Show full solutionCorrect option: B
Correct answer
BPropanal as substrate and methanol in excess

Step-by-step explanation

Acetal is form from the reaction of aldehyde with excess of MeOH

Formation of an acetal occurs when the hydroxyl group of a hemiacetal becomes protonated and is lost as water. The carbocation that is produced is then rapidly attacked by a molecule of alcohol. Loss of the proton from the attached alcohol gives the acetal.

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About this question

This is a previous-year question from JEE Main 2019, covering the Aldehydes and Ketones 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.