Explain why p-nitrophenol is more acidic than phenol?
Nitro group of phenol produces I and effect. Because of these two effects — group is electron withdrawing in nature. So, the electron density in the O—H bond of p-nitrophenol decreases relative to the O— H bond of phenol.
The decrease in electron density of the O—H bond of p-nitrophenol, the polarity of O—H bond is decrease and in turn make it more acidic than phenol.