JEE Chemistry 2024 Question with Solution

Given: The options compare aromatic, anti-aromatic, and non-aromatic species in terms of stability.

Find: Which molecule/species is the most stable.

Identify principle: Aromatic compounds are exceptionally stable because of cyclic delocalization of $\pi$-electrons and satisfaction of H"uckel's rule.

From the solution text:

1. Aromatic species have additional stability due to delocalized $\pi$-electrons.
2. The aromatic option satisfies the $4n + 2$ rule and has a planar conjugated ring structure.
3. Anti-aromatic and non-aromatic species do not get this extra aromatic stabilization.

The solution working states that the aromatic species is the most stable. Although the solution says Option C and the final sentence says Option (3), this contradicts the actual explanation, which clearly identifies Option (1) Aromatic compound as the most stable species.

Therefore, the correct option is A.

Given:

• Option (1): Aromatic compound
• Option (2): Anti-aromatic compound
• Option (3): Non-aromatic compound
• Option (4): All are equally stable

Find: The most stable species.

Apply concept: Stability order is governed by aromatic character.

• Aromatic compounds are most stable because they are cyclic, planar, conjugated, and follow

$\pi$-electron count.

• Anti-aromatic compounds are destabilized because they are cyclic, planar, conjugated, but follow

$\pi$-electron count.

• Non-aromatic compounds lack the special stabilization of aromatic compounds.

Hence, among the listed categories, the aromatic compound is the most stable.

Therefore, the correct option is A.