JEE Main 2022 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 27 July 2022, Shift 1, Chemistry Q89

Question 89 of 90 in this shift, Chemistry question 29 of 30, Section B.

Optical activity of an enantiomeric mixture is

+12.6^\circ

and the specific rotation of (+) isomer is

+30^\circ

. The optical purity is _____%.

Official answer

NTA final key.

Chapter: Haloalkanes and Haloarenes
Topic: Stereoisomerism
Idea tested: Enantiomeric Excess and Specific Rotation

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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. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.