Question

Given below are two statements : 
Statement I : Hyperconjugation is not a permanent effect. 
Statement II : In general, greater the number of alkyl groups attached to a positively charged C-atom, greater is the hyperconjugation interaction and stabilization of the cation. 
In the light of the above statements, choose the correct answer from the options given below

• A. Statement I is true but Statement II is false
• B. Both Statement I and Statement II are false
• C. Statement I is false but Statement II is true
• D. Both Statement I and Statement II are true

Hint:

Hyperconjugation is a permanent stabilizing effect involving the delocalization of sigma (\( \sigma \)) electrons. The extent of hyperconjugation is directly proportional to the number of \( \alpha \)-hydrogen atoms (hydrogen atoms on the carbon atom adjacent to the carbocation, radical, or alkene). More \( \alpha \)-hydrogens lead to greater stabilization.

Answer 1

The Correct Option is C

Statement I : Hyperconjugation is not a permanent effect. Hyperconjugation is a permanent effect that involves the delocalization of \( \sigma \)-electrons of a C-H bond of an alkyl group directly attached to an unsaturated system or to an atom with an unshared p-orbital. 
This delocalization occurs even in the absence of an external reagent or condition. 
Therefore, Statement I is false. Statement II : In general, greater the number of alkyl groups attached to a positively charged C-atom, greater is the hyperconjugation interaction and stabilization of the cation. 
A carbocation is stabilized by hyperconjugation due to the donation of \( \sigma \)-electrons from the adjacent C-H bonds. Alkyl groups attached to the positively charged carbon atom have C-H bonds that can participate in hyperconjugation. The more alkyl groups attached, the greater the number of \( \alpha \)-hydrogen atoms available for hyperconjugation. 
This leads to greater delocalization of the positive charge and hence greater stability of the carbocation. 
Therefore, Statement II is true. In conclusion, Statement I is false, but Statement II is true. This corresponds to option (3).