See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# π e⁻ Density in Aromatic Rings ## Part (i): Decreasing order of π e⁻ density **Analysis of substituent effects:** - **(A) Nitrobenzene ($NO_2$)**: Electron-withdrawing group (EWG) → *decreases* π e⁻ density on ring - **(B) Anisole ($OCH_3$)**: Electron-donating group (EDG) via resonance → *increases* π e⁻ density - **(C) Aniline ($NH_2$)**: Strong EDG (lone pair on N) → *greatly increases* π e⁻ density - **(D) Dinitrobenzene ($NO_2$ × 2)**: Two EWGs → *severely depletes* π e⁻ density **Correct order (decreasing π e⁻ density):** $$\boxed{\text{C} > \text{B} > \text{A} > \text{D}}$$ (Aniline > Anisole > Nitrobenzene > Dinitrobenzene) --- ## Part (ii): Decreasing order of π e⁻ density **Analysis:** - **(A) Nitrobenzene ($NO_2$)**: EWG → low π density - **(B) Phenoxide anion ($O^⊖$)**: Negatively charged oxygen donates electron density strongly → *highest* π density - **(C) Aniline ($NH_2$)**: Strong EDG → high π density - **(D) Anisole ($OCH_3$)**: Moderate EDG → moderate π density **Correct order (decreasing π e⁻ density):** $$\boxed{\text{B} > \text{C} > \text{D} > \text{A}}$$ (Phenoxide > Aniline > Anisole > Nitrobenzene) The negatively charged oxygen in (B) is the strongest electron donor, making it rank first.