JEE Chemistry 2023 Question with Solution

Given: Assertion states that benzene is more stable than hypothetical cyclohexatriene. Reason states that the delocalized $\pi$ electron cloud is strongly attracted by the nuclei of carbon atoms.

Find: Which option correctly relates the assertion and reason.

Benzene is more stable than hypothetical cyclohexatriene because of resonance stabilization. The delocalization of $\pi$ electrons in benzene creates extra stability compared to isolated double bonds in cyclohexatriene.

The delocalized $\pi$ electron cloud in benzene forms a bonding molecular orbital, which is strongly attracted by the nuclei of the carbon atoms, resulting in additional stabilization.

Therefore, both Assertion and Reason are correct, and Reason is the correct explanation of Assertion. The correct option is D.

The solution's lists Correct Answer: (3), but the extracted solution concludes D. Since the solution is the primary source, D is taken as correct.

Given: Benzene and hypothetical cyclohexatriene are being compared on the basis of stability.

Find: Whether the stated reason explains the higher stability of benzene.

In benzene, the $\pi$ electrons are delocalized over the ring rather than being confined to three separate double bonds. This delocalization lowers the overall energy of the molecule and gives resonance stabilization.

Because this delocalized electron cloud is spread over the carbon framework, it experiences stabilizing attraction from the carbon nuclei throughout the ring. Hence the reason directly accounts for the unusual stability of benzene.

Therefore, both statements are true, and the reason correctly explains the assertion. The correct option is D.