See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Resonance Energy Comparison **Step 1: Identify the structures** - **(I)** Pyrrole: 5-membered aromatic ring with N-H (aromatic heterocycle) - **(II)** Furan: 5-membered aromatic ring with O (aromatic heterocycle) - **(III)** Divinyl amine: $CH_2=CH-NH-CH=CH_2$ (non-aromatic, open chain) **Step 2: Assess aromaticity and resonance stability** Compounds (I) and (II) are **aromatic** with significant delocalization: - **Pyrrole (I)**: The lone pair on N participates in the $\pi$-system, achieving aromaticity. This contributes strong resonance stabilization. - **Furan (II)**: The lone pair on O participates in the $\pi$-system, but O is more electronegative. Oxygen less readily donates its lone pair compared to N, resulting in weaker resonance. **Step 3: Compare aromaticity strength** Pyrrole shows **greater aromaticity** than furan because: - N is less electronegative than O → more readily donates lone pair - Better resonance stabilization in pyrrole **Step 4: Evaluate divinyl amine (III)** - **Non-aromatic**: Open-chain structure with isolated $C=C$ bonds - **Minimal resonance**: Only weak allylic conjugation - **Lowest resonance energy** **Step 5: Order of resonance energy** $$\text{(I) > (II) > (III)}$$ **Answer: (B)** — Pyrrole exhibits the strongest resonance stabilization due to efficient N lone-pair donation in the aromatic system, followed by furan, while divinyl amine lacks significant aromatic resonance.