Question

The correct acidity order of the following is:

• A. $\left(III\right)>\left(IV\right)>\left(II\right)>\left(I\right)$
• B. $\left(IV\right)>\left(III\right)>\left(I\right)>\left(II\right)$
• C. $\left(II\right)>\left(III\right)>\left(IV\right)>\left(I\right)$
• D. $\left(III\right)>\left(II\right)>\left(I\right)>\left(IV\right)$

Answer 1

Answer: (A)

Decreasing order of acidic strength is $III>IV>II>I$

Carboxylic acid is more acidic than phenol. When an electron releasing group is present in the para position to -COOH group in aromatic carboxylic acid, the acidity is reduced.

When Cl atom is present in the para position to -OH group in phenol, it increases its acidity.

Here Cl atom withdraws electron density from the ring and stabilizes the phenoxide ion.

Option A is correct.