Mark the correct order of decreasing acid strength of the following compounds.
(a)
(b)
(c)
(d)
(e)
The presence of electron-withdrawing group(e.g. nitro group), enhances the acidic strength of phenol.It is due to the effective delocalization of negative charge in phenoxide ion.
On the other hand, electron releasing groups (e.g. -OCH3) in general, do not favour the formation of phenoxide ion resulting in a decrease in the acidic nature.
The effect is more when the substituent group is more at the ortho position or para position in comparison to the meta position.
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