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Organic Chemistry – Some Basic Principles and Techniques · Question 31

JEE Main 2025 (Online) 3rd April Evening ShiftMCQEasy📈 Topic in 10% papers+4−1
1

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. Statement I is true but Statement II is false
  3. Both Statement I and Statement II are false
  4. Both Statement I and Statement II are true

Answer

(1) Statement I is false but Statement II is true

Solution

Statement I:

As per NCERT, hyperconjugation is a general stabilising interaction that involves delocalisation of σ electrons of a C–H bond of an alkyl group attached to an unsaturated system or to an atom with an unshared p orbital. It is a permanent effect. Statement I is false.

Statement II:

More alkyl groups on the positively charged carbon more α C–H bonds more hyperconjugation structures greater stability.

(CH3)3 C > (CH3)2 CH > CH3 CH2 > CH3

Statement II is true.

Answer: (1)

JEE Main 2025 (Online) 3rd April Evening Shift

Keep practising — Organic Chemistry – Some Basic Principles and Techniques

2

Consider the following compound (X) [figure] The most stable and least stable carbon radicals, respectively, produced by homolytic cleavage of corresponding C-H bond are :

  1. III, II
  2. II, IV
  3. I, IV
  4. II, I
JEE Main 2025 (Online) 2nd April Morning Shift
3

Designate whether each of the following compounds is aromatic or not aromatic. [figure]

  1. a, c, d, e, h aromatic and b, f, g not aromatic
  2. b, e, f, g aromatic and a, c, d, h not aromatic
  3. a, b, c, d aromatic and e, f, g, h not aromatic
  4. e, g aromatic and a, b, c, d, f, h not aromatic
JEE Main 2025 (Online) 2nd April Morning Shift
4

In 3,3-dimethylhex-1-en-4-yne, there are sp3, sp2 and sp hybridised carbon atoms respectively.

  1. 4, 2, 2
  2. 2, 4, 2
  3. 3, 3, 2
  4. 2, 2, 4
JEE Main 2025 (Online) 2nd April Evening Shift
5

Match List - I with List - II. Choose the correct answer from the options given below :

  1. (A)-(II), (B)-(III), (C)-(IV), (D)-(I)
  2. (A)-(II), (B)-(III), (C)-(I), (D)-(IV)
  3. (A)-(III), (B)-(IV), (C)-(I), (D)-(II)
  4. (A)-(III), (B)-(II), (C)-(I), (D)-(IV)
JEE Main 2025 (Online) 29th January Morning Shift
6

Total number of nucleophiles from the following is : NH3, PhSH, (H3C)2S, H2C=CH2, OH, H3O , (CH3)2 CO, [figure]

  1. 4
  2. 6
  3. 5
  4. 7
JEE Main 2025 (Online) 29th January Morning Shift
7

The correct order of stability of following carbocations is : [figure]

  1. A > B > C > D
  2. C > B > A > D
  3. B > C > A > D
  4. C > A > B > D
JEE Main 2025 (Online) 28th January Morning Shift

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