Q. Which of the following acids has the smallest dissociation constant?
A) $CH_{3}CHFCOOH$
B) ${FCH}_{2}\ {CH}_{2}\ COOH$
C) $BrCH_{2}CH_{2}COOH$
D) $CH_{3}CHBrCOOH$
Explanation
(c)
Group or atom attached with $–COOH$ group shows negative inductive effect, makes the acid stronger or acid has larger dissociation constant. $–Br$ shows poor negative inductive effect and also far away from $–COOH$, which makes $BrCH_{2}CH_{2}COOH$ weakest acid and hence, it has smallest dissociation constant.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.