Four aromatic compounds are independently introduced into liquid water at 25 °C: phenol (C₆H₅OH), anisole (C₆H₅OCH₃), para-nitrophenol (p-O₂NC₆H₄OH), and ortho-nitrophenol (o-O₂NC₆H₄OH). Assume no acid–base reactions occur and that only physical dissolution is considered.
(a) Arrange the four compounds in order of decreasing molar solubility in water.
(b) For each compound, discuss at the molecular level how electronic effects (inductive and resonance), hydrogen-bond donor/acceptor capacity, and potential intramolecular hydrogen bonding affect its interaction with water.
(c) Propose a single structural modification to anisole that would significantly increase its solubility in water, and justify how the modification would enhance specific intermolecular interactions with the solvent.