Which of the following acids has the smallest dissociation c... | CHEMISTRY - METHODS OF PREPARATION OF CARBOXYLIC ACIDS | SolveeIt | Solveeit

Today, August 18

Question

Which of the following acids has the smallest dissociation constant

A

$\mathrm { CH } _ { 3 } \mathrm { CHFCOOH }$

B

$\mathrm { FCH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { COOH }$

C

$\mathrm { BrCH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { COOH }$

D

$\mathrm { CH } _ { 3 } \mathrm { CHBrCOOH }$

Answer

$\mathrm { BrCH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { COOH }$

Explanation

Solution

$K _ { a }$ i.e., dissociation constant. It is (1) due to lesser –I effect of Br than F and (2) Br atom further away form group.