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Isomerism

JEE Main 2026 (Online) 21st January Evening ShiftMCQEasy📈 Topic in 8% papers+4−1
Ques. 1JEE Main 2026, 21 January (Evening Shift)

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)

Keep practising — Isomerism

Ques. 2JEE Main 2025, 7 April (Evening Shift)

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
Ques. 3JEE Main 2025, 7 April (Evening Shift)

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
Ques. 4JEE Main 2025, 3 April (Morning Shift)

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
Ques. 5JEE Main 2025, 3 April (Evening Shift)

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

Ques. 6JEE Main 2025, 28 January (Evening Shift)

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
Ques. 7JEE Main 2025, 24 January (Evening Shift)

The possible number of stereoisomers for 5-phenylpent-4-en-2-ol is .

Ques. 8JEE Main 2025, 22 January (Morning Shift)

How many different stereoisomers are possible for the given molecule? [figure]

  1. 2
  2. 1
  3. 3
  4. 4
Ques. 9JEE Main 2025, 22 January (Morning Shift)

The incorrect statements regarding geometrical isomerism are : Choose the correct answer from the options given below :

  1. A and E Only
  2. A, D and E Only
  3. C, D and E Only
  4. B and C Only
Ques. 10JEE Main 2024, 9 April (Evening Shift)

Total number of stereo isomers possible for the given structure : [figure]

  1. 4
  2. 2
  3. 8
  4. 3
Ques. 11JEE Main 2024, 8 April (Morning Shift)

The number of optical isomers in following compound is : . [figure]

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