See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Carbocation Stability Analysis **Stability factors for carbocations:** 1. Alkyl substitution at the positive carbon (more alkyl groups → greater stability) 2. Resonance stabilization from adjacent aromatic rings or electron-donating groups --- **Analyzing each carbocation:** **(a)** $CH_3O-\text{(benzene)}-CH_2^+$ - Benzyl carbocation (primary, but stabilized by resonance with benzene ring) - **Strong resonance stabilization** from aromatic ring - Highest stability ✓ **(b)** Benzyl carbocation $\text{(benzene)}-CH_2^+$ - Primary carbocation with aromatic resonance - **Good stability** but lacks the electron-donating $OCH_3$ group of (a) **(c)** $CH_3-\text{(benzene)}-CH_2^+$ - Benzyl carbocation with electron-donating $CH_3$ (weak donor) - **Slightly more stable than (b)** due to inductive effect of methyl **(d)** $CH_3-CH_2^+$ (ethyl carbocation) - Primary aliphatic carbocation - **No resonance stabilization**, weakest stability --- **Stability order:** $d < b < c < a$ **Reasoning:** (d) is least stable (primary aliphatic). Among aromatic carbocations, (b) < (c) because methyl is weakly electron-donating. (a) is most stable due to strong electron-donation from methoxy ($-OCH_3$) group, which stabilizes the positive charge through resonance. **Answer: (A)**