Q. What is the correct increasing order of extent of deprotonation of the following acids in its aqueous solution?
(I)
(II)
(III)
(IV)

 2355  194 Organic Chemistry – Some Basic Principles and Techniques Report Error

Solution:

Electron withdrawing group increases acidic strength while electron donating group decreases acidic strength. Also magnitude of inductive effect decreases drastically on increasing distance, is stronger acid than .

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Two methyl groups (in ) gives greater effect than one methyl group (in ), hence I is a weaker acid than .

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Two from closer position in exert greater-I effect than the same from larger distance in , hence is stronger acid than .