Question

Arrange the following in increasing order of acidic strength

• A. III < V < IV < II < I
• B. V < IV < III < II < I
• C. III < II < IV < I < V
• D. I < II < III < IV < V

Answer 1

Answer: (A)

Acidic nature of sulphonic acid is more than that of carboxylic acid and carboxylic acid is more acidic then an alcohol.

Acidic nature $ \propto $ electron withdrawing group $ \propto \frac{\text{1}}{\text{electron} \, \text{releasing} \, \text{group}}$ .

Here the correct order of acidic nature is III < V < IV < II < I.