JEE Main 2021 · ChemistryMultiple choiceSingle correctEasyConceptual

JEE Main 18 March 2021, Shift 1, Chemistry Q42

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

Compound with molecular formula

\mathrm{C_3H_6O}

can show :

(1)Positional isomerism
(2)Functional group isomerismOfficial answer
(3)Metamerism
(4)Both positional isomerism and metamerism

Official answer

Option 2

NTA final key.

Chapter: Organic Chemistry: Some Basic Principles and Techniques
Topic: Structural Isomerism
Idea tested: Functional Isomerism

Same topic in other shifts

All Structural Isomerism questions

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6 Apr 2026, Shift 1 · Q64Given below are two statements: Statement I: 2,6-diethylcyclohexanone and 6-methyl-2-n-propylcyclohexanone are metamers. Statement II:…MediumTwo statements
3 Apr 2025, Shift 1 · Q64Identify the correct statements from the following. A. [structure: pentan-3-one (skeletal, C=O at the middle carbon)] and [structure:…MediumOtherHas a figure
3 Apr 2025, Shift 2 · Q75The total number of structural isomers possible for the substituted benzene derivatives with the molecular formula $\mathrm{C_9H_{12}}$ is…MediumNumerical value

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 42 of the 174 JEE Main shifts held from 2017 to 2026.