The compound/s which will show significant intermolecular H-bonding is/are :

Solution

Chemistry ma’am · 2 steps

Having an O–H is not enough: ask whether that O–H can actually reach a neighbouring molecule.

1. What to check. Intermolecular H-bonding needs an O–H or N–H on one molecule to reach an O or N on another. If that H is already bonded inside its own molecule, or is buried under bulky groups, it cannot do this.

   Compound	H-bond donor	What happens to it	Significant intermolecular H-bond?
   (a) o-nitrophenol	O–H next to NO₂	Forms a six-membered ring with the nearby nitro oxygen, so it is an intramolecular H-bond	No
   (b) paracetamol	O–H and N–H at opposite ends (para)	Too far apart to bond to each other, so both are free to bond to the C=O and O–H of other molecules	Yes
   (c) 2,6-di-tert-butyl-4-methylphenol	O–H between two tert-butyl groups	The two bulky C(CH₃)₃ groups shield the O–H, so other molecules cannot get close (steric hindrance)	No

2. So. Only compound (b) shows significant intermolecular H-bonding. That is option (a), "(b) only".

The idea to keep. Find the O–H or N–H, then ask two things: is an acceptor right next to it (intramolecular, like ortho groups), and is it shielded by bulky groups? Either one shuts off intermolecular H-bonding.

Answer from the NTA final answer key. Solution by PrepWiser.