Question 13
Given the following information, which of these acids is the weakest?
$K_a$ of boric acid is $7.3 \times 10^{-10}$
$pK_a$ of acetic acid is 4.75.
$K_a$ of lactic acid is $8.4 \times 10^{-4}$.
$pK_a$ of phenol is 9.89.
acetic acid
formic acid
lactic acid
phenol