See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Order of Ease of Hydrogen Removal **Step 1: Identify hydrogen types** - $H_1$: aromatic hydrogen (on benzene ring) - $H_2$: benzylic hydrogen (on carbon attached to benzene) - $H_3$: allylic hydrogen (on carbon next to $H_2$) - $H_4$: primary hydrogen (on terminal $CH_2$) **Step 2: Apply stability of resulting carbocation/radical** Ease of H removal depends on stability of the carbocation formed (or radical in radical substitution): $$\text{Benzylic}^+ > \text{Allylic}^+ > \text{Primary}^+ > \text{Aromatic H (very hard)}$$ **Step 3: Rank each hydrogen** - $H_2$ (benzylic): Forms resonance-stabilized benzylic carbocation → **easiest to remove** - $H_3$ (allylic): Forms resonance-stabilized allylic carbocation → **second easiest** - $H_4$ (primary): Forms simple primary carbocation → **third** - $H_1$ (aromatic): Breaking aromatic stability is extremely unfavorable → **hardest to remove** **Step 4: Conclude** $$H_2 > H_3 > H_4 > H_1$$ **Answer: (B)** ✓ The benzylic position is most reactive due to resonance stabilization by the adjacent benzene ring, while aromatic hydrogens are most stable and least likely to be removed.