Arrange the following compounds in the increasing order of their acidic strength:
i. M – nitrophenol
ii. M – cresol
iii. Phenol
iv. M – cholorophenol
ii < iii < iv <i
m-cresol has electron releasing group (CH3). Hence it decreases the acidic strength. Both nitro and chloro are having – I effect. Hence, they show higher acidic strength. But nitro is a stronger – I group than chloro group. Hence m-Nitro phenol is more acidic than m-chlorophenol