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Chemistry Question 63 – JEE-MAIN 2026

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Given below are two statements: Statement I: On the basis of inductive effect, the order of stability of alkyl carbanions is CH3−>CH3CH2−>(CH3)2CH−>(CH3)3C−. Statement II: Allyl and benzyl carbanions are more stabilised by inductive effect and not by resonance effect. In the light of the above statements, choose the correct answer from the options given below

Understand how electron-donating and electron-withdrawing groups affect the stability of carbanions.

Step 1: Analyze Statement I: Stability of Alkyl Carbanions✦ Active

Carbanions are stabilized by electron-withdrawing groups and destabilized by electron-donating groups. Alkyl groups exhibit a positive inductive effect (+I), meaning they donate electrons. Therefore, increasing the number of alkyl groups attached to the carbanionic carbon will destabilize the carbanion by intensifying the negative charge.

The order of stability based on inductive effect is: CH3−>CH3CH2−>(CH3)2CH−>(CH3)3C−. This order is correctly stated in Statement I.

💡 Teacher's Secret Hint

Remember that carbanions are electron-rich species, so anything that disperses the negative charge stabilizes them, and anything that concentrates it destabilizes them.

Step 2: Analyze Statement II: Stability of Allyl and Benzyl Carbanions○ Expand

Allyl carbanion (CH2=CH−CH2−) and benzyl carbanion (C6H5−CH2−) both possess a negative charge adjacent to a π-system (double bond or aromatic ring). This allows for the delocalization of the negative charge through resonance.

Resonance stabilization is a much stronger effect than inductive effect in these cases. Statement II claims they are stabilized by inductive effect and not by resonance, which is incorrect.

💡 Teacher's Secret Hint

Always prioritize resonance over inductive effects when both are possible, as resonance provides significantly greater stabilization due to charge delocalization.

Step 3: Conclusion○ Expand

Based on the analysis, Statement I is correct, and Statement II is incorrect.

Therefore, the correct option is 'Statement I is correct but Statement II is incorrect'.

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