This question relates to the reactivity of alkyl/aryl halides towards nucleophilic substitution. C₆H₅CHClC₆H₅ (diphenylmethyl chloride) is a secondary benzylic halide, while C₆H₅CH₂Cl (benzyl chloride) is a primary benzylic halide. The hydrolysis with aqueous KOH proceeds via S_N1 mechanism for benzylic halides due to resonance stabilization of the carbocation intermediate. The carbocation formed from C₆H₅CHClC₆H₅ is more stable because the positive charge can be delocalized over two phenyl rings, providing greater resonance stabilization compared to the primary benzylic carbocation from C₆H₅CH₂Cl which has only one phenyl ring for stabilization. Greater carbocation stability leads to faster S_N1 reaction, making C₆H₅CHClC₆H₅ more reactive towards hydrolysis.