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Isomerism · Question 9

JEE Main 2026 (Online) 21st January Evening ShiftMCQEasy📈 Topic in 10% papers+4−1
1

Given below are four compounds : (a) n-propyl chloride (b) isopropyl chloride (c) sec-butyl chloride (d) neopentyl chloride Percentage of carbon in the one which exhibits optical isomerism is :

  1. 46
  2. 40
  3. 52
  4. 56

Answer

(3) 52

Solution

(a) CH3-CH2-CH2-Cl: no chiral carbon

(b) (CH3)2CH-Cl: two identical CH3 groups on C – no chiral carbon

(c) CH3-CH2-CH(Cl)-CH3: C-2 carries H, Cl, CH3 and C2H5 chiral, shows optical isomerism

(d) (CH3)3C-CH2-Cl: no chiral carbon

sec-Butyl chloride, C4H9Cl: molar mass = 4(12) + 9(1) + 35.5 = 92.5 g mol-1

\% C = 4892.5 100 = 51.9 52

Answer: (3)

JEE Main 2026 (Online) 21st January Evening Shift

Keep practising — Isomerism

2

The number of optically active products obtained from the complete ozonolysis of the given compound is : [figure]

  1. 4
  2. 0
  3. 2
  4. 1
JEE Main 2025 (Online) 7th April Evening Shift
3

Given below are two statements : In the light of the above statements, choose the most appropriate answer from the options given below :

  1. Both Statement I and Statement II are correct
  2. Statement I is incorrect but Statement II is correct
  3. Both Statement I and Statement II are incorrect
  4. Statement I is correct but Statement II is incorrect
JEE Main 2025 (Online) 7th April Evening Shift
4

Identify the correct statements from the following. Choose the correct answer from the options given below:

  1. B & C Only
  2. C & D Only
  3. A,B & C Only
  4. A & B Only
JEE Main 2025 (Online) 3rd April Morning Shift
5

The total number of structural isomers possible for the substituted benzene derivatives with the molecular formula C9H12 is .

JEE Main 2025 (Online) 3rd April Evening Shift
6

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

  1. Statement I is false but Statement II is true
  2. Both Statement I and Statement II are true
  3. Statement I is true but Statement II is false
  4. Both Statement I and Statement II are false
JEE Main 2025 (Online) 28th January Evening Shift

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All JEE Main Chemistry chapters
Physical ChemistrySome Basic Concepts of ChemistryStructure of AtomStates of MatterThermodynamicsEquilibriumRedox ReactionsSolutionsElectrochemistryChemical Kinetics
Inorganic ChemistryClassification of Elements and Periodicity in PropertiesChemical Bonding and Molecular Structurep-Block Elements (Group 13 & 14)p-Block Elements (Group 15–18)d- and f-Block ElementsCoordination Compounds
Organic ChemistryOrganic Chemistry – Some Basic Principles and TechniquesIsomerismHydrocarbonsHaloalkanes and HaloarenesAlcohols, Phenols and EthersAldehydes, Ketones and Carboxylic AcidsAminesBiomoleculesPrinciples Related to Practical Chemistry