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Saturday, 31 October

JEE Main 2022 · ChemistryMultiple choiceDiagram basedHardMulti-step

JEE Main 28 July 2022, Shift 2, Chemistry Q42

Question 42 of 90 in this shift, Chemistry question 12 of 30, Section A.

The major product in the given reaction is [reaction: line structure of an unsaturated tertiary alcohol, alkene with two methyl groups at the left end and a tertiary carbon bearing OH at the right end] →(1) H+, heat; (2) HBr\xrightarrow{(1)\ \mathrm{H^+},\ \text{heat};\ (2)\ \mathrm{HBr}}

The figure, in words

Line-bond structure of an unsaturated tertiary alcohol: alkene with two terminal methyl groups at left, chain, and -C(CH3)2-OH at right, reagents (1) H+, heat (2) HBr. Options are line structures; in options A and B the halogen label is printed as "B2" (apparently Br); C and D print "Br".
  1. (1)[figure: open-chain line structure, alkene at left end, tertiary carbon at right end bearing a substituent printed "B2"]
  2. (2)[figure: cyclopentane ring with a gem-dimethyl carbon and an adjacent carbon with methyl groups and a substituent printed "B2"]
  3. (3)[figure: cyclopentane ring with methyl groups on ring carbons and a substituent printed "Br" on a side-chain carbon]Official answer
  4. (4)[figure: open-chain saturated line structure with a substituent printed "Br" and methyl branches at both ends]

Official answer

Option 3

NTA final key.

Chapter
Alcohols, Phenols and Ethers
Topic
No close match in our taxonomy
Idea tested
No close match in our taxonomy

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.