Question

Which one of the following have least ${}_P{K}_a$ value?

• A. $CC{l}_{3}COOH$
• B. $C{H}_{2}ClCOOH$
• C. $C{F}_{3}COOH$
• D. $C{H}_{3}COOH$

Answer 1

Answer: (C)

$C{F}_{3}COOH$ is the strongest acid due to greatest $-I$ effect of $F$ atom among $Cl$ and $C{H}_3$ .