Given below are two statements : Statement I : (CH₃)₃C⁺ is more stable than CH₃⁺ as nine hyperconjugation interactions are possible in (CH₃)₃C⁺. Statement II : CH₃⁺ is less stable than (CH₃)₃C⁺ as only three hyperconjugation interactions are possible in CH₃⁺. In the light of the above statements, choose the correct answer from the options given below.

Given below are two statements about stability of carbocations and hyperconjugation

Q. Given below are two statements :

Statement I : (CH₃)₃C⁺ is more stable than CH₃⁺ as nine hyperconjugation interactions are possible in (CH₃)₃C⁺.

Statement II : CH₃⁺ is less stable than (CH₃)₃C⁺ as only three hyperconjugation interactions are possible in CH₃⁺.

In the light of the above statements, choose the correct answer from the options given below

A. Statement I is false but Statement II is true

B. Statement I is true but Statement II is false

C. Both Statement I and Statement II are true

D. Both Statement I and Statement II are false

Correct Answer: Statement I is true but Statement II is false

Explanation

Carbocation stability increases with increase in number of hyperconjugative structures.

Statement I:
In tert-butyl carbocation, (CH₃)₃C⁺, there are three methyl groups attached to the positively charged carbon.

Each methyl group has three α-hydrogen atoms. Hence, total hyperconjugation interactions possible are:

$$ 3 \times 3 = 9 $$

Therefore, (CH₃)₃C⁺ is highly stabilized due to nine hyperconjugative structures. Statement I is correct.

Statement II:
In methyl carbocation, CH₃⁺, there are no adjacent carbon atoms and hence no α-hydrogen atoms.

Therefore, zero hyperconjugation interactions are possible in CH₃⁺, not three.

Thus, the reason given in Statement II is incorrect, although the stability order is correct.

Hence, Statement I is true but Statement II is false.

Explanation

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