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Two statements are given, one labelled Assertion (A) and the other Reason (R). Assertion A: Benzene is more stable than the hypothetical molecule cyclohexatriene. Reason R: The delocalized pi-electron cloud is held more strongly by the carbon nuclei. Choose the correct option.

1. A is true but R is false.
2. A is false but R is true.
3. Both A and R are correct and R is the correct explanation of A.
4. Both A and R are correct but R is NOT the correct explanation of A.

Correct answer: Both A and R are correct and R is the correct explanation of A.

Solution

Benzene's six pi electrons are delocalized over all six carbons, giving resonance (delocalization) energy, so benzene is genuinely more stable than localized cyclohexatriene; A is true. The reason that the delocalized cloud is more strongly attracted/held by the carbon nuclei correctly describes why delocalization lowers energy; R is true and correctly explains A.

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