See image — Aromatic Hydrocarbons Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the reagents: The reaction uses HNO2 (nitrous acid) and HNO3 (nitric acid) acting together on toluene. This combination is known to effect oxidative nitration. In this context, HNO2/HNO3 can oxidize the methyl group of toluene to an OH group (side-chain oxidation to phenol) while simultaneously introducing a nitro group onto the ring, or alternatively the system acts via electrophilic aromatic nitration followed by oxidation. The net transformation converts toluene (C6H5CH3) into a nitrophenol. Step 2 - Direction of substitution: The methyl group on toluene is an ortho/para director. When the methyl group is oxidized to OH (also a strong ortho/para director), the nitro group is directed to the para position relative to OH. Para substitution is generally favored over ortho due to steric reasons, giving the major product as 4-nitrophenol. Step 3 - Identify major product: 4-Nitrophenol has OH at C1 and NO2 at C4. This corresponds to option (c). Step 4 - Why other options fail: - Option (a): Shows a nitroso (NO) group, not a nitro (NO2) group; HNO3 provides nitro groups, not nitroso. - Option (b): 2-Nitrophenol is the ortho product; para is the major product due to lower steric hindrance. - Option (d): 3-Nitrophenol would result from a meta director; neither CH3 nor OH is a meta director. Therefore, the correct answer is C.