The HF2^- ion exists in the solid state & also in liquid state but not in aqueous state. — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Ortho-nitrophenol has adjacent hydroxyl (-OH) and nitro (-NO2) groups, allowing it to form stable intramolecular (within-molecule) hydrogen bonds. This chelating effect prevents it from forming hydrogen bonds with neighboring molecules. Step 2: Para-nitrophenol has these groups far apart and can only form intermolecular hydrogen bonds, leading to extensive molecular association and a higher boiling point. Thus, ortho-nitrophenol is more volatile and can be easily steam distilled. Step 3: Therefore, this difference in steam distillation is due to the strong intramolecular hydrogen bonding in o-nitrophenol, matching option (b).