o-nitrophenol and p-nitrophenol differ in that they show, respectively:

1. In o-nitrophenol the nitro group sits next to the hydroxyl group on the ring. 2. They are close enough to bond to each other within the same molecule, which is intramolecular hydrogen bonding. 3. In p-nitrophenol the two groups sit opposite each other, too far apart to reach within one molecule. 4. So p-nitrophenol bonds instead to neighbouring molecules, which is intermolecular hydrogen bonding. 5. Writing 'intrahydrogen' and 'interhydrogen' instead of intramolecular and intermolecular was a recorded wording error. _Source: NECTA ACSEE 2023 Chemistry 132/1, Question 3: Chemical Bonding_