(c) The correct order of increasing acidic strength is : ethanol < phenol < acetic acid < chloroacetic acid Phenol is more acidic than ethanol because in phenol, the phenoxide ion obtained on deprotonation is stabilised by resonance, which is not possible in case on ethanol. Also carboxylic acids are more acidic than alcohols and phenols as the carboxylate ion is stabilised by resonance. Chloroacetic acid is more acidic than acetic acid due to inductive effect of chlorine atom which stabilises the carboxylate anion.