Question

) Arrange the follwowing compounds in the increasing order of their strength: p-cresol, p-nitrophenol, phenol.

Answer 1

p-Nitrophenol > phenol > p-cresol

Reason:

Nitro group in para nitrophenol applies -m effect that is lone pair attracting effect and brings complete positive charge on its ortho and para position . On the para position of nitro group carbon atom is hydroxy group carbon atom. The positive charge on this carbon is unstable and hence it attracts the lone pair of oxygen thus weakening the oxygen and hydrogen bond and increasing the acidic strength.