WHAT IS THE ORDER OF INCREASING ACIDITY FOR THE FOLLOWING CO

WHAT IS THE ORDER OF INCREASING ACIDITY FOR THE FOLLOWING COMPOUNDS? (LEAST ACIDIC TO FIRST) IN A SHORT PARAGRAPH , EXLPLAIN YOUR ORDERING.

Solution

4>2>3>1

4 has the resonance electron pulling effect

Cl at the para position can push electron to the benzene ring (+R effect) thus decreasing the acidity of the -OH center.

CH3 at the para position impose weak + inductive effect

whether -H at para has no such effect

I hope it explains the order I have given.