Bond order can assume any value including zero. — Chemical Bonding Chemistry Question

💡 Solution & Explanation

Step 1: Compound A is para-nitrophenol, which exhibits intermolecular hydrogen bonding, whereas Compound B is ortho-nitrophenol, which exhibits intramolecular hydrogen bonding. Step 2: Intramolecular hydrogen bonding in ortho-nitrophenol (B) prevents it from forming hydrogen bonds with neighboring molecules, making it highly volatile with a higher vapour pressure. In contrast, intermolecular hydrogen bonding in para-nitrophenol (A) causes strong association between molecules, lowering its vapour pressure. Step 3: Thus, the vapour pressure of B is higher than that of A, matching option (a).