# Question #e80d3

Oct 22, 2017

Acetic acid.

#### Explanation:

To find the conjugate acid of a Bronsted - Lowry base, you add a proton, ${\text{H}}^{+}$, to the chemical formula of the base.

Keep in mind that because you're adding a proton and not a hydrogen atom, $\text{H}$, you need to keep track of the charge of the conjugate acid as well.

In this case, your Bronsted - Lowry base is the acetate anion, ${\text{CH"_3"COO}}^{-}$. Notice that this anion carries a $1 -$ charge, so right from the start, you know that after you add the proton, the resulting compound will be electrically neutral.

${\overbrace{\left(1 -\right)}}^{\textcolor{b l u e}{{\text{starting charge")) + overbrace((1+))^(color(blue)("charge of H}}^{+}}} = 0$

You can thus say that you have

$\text{CH"_ 3"COO"^(-) + "H"^(+) -> "CH"_ 3"COOH}$

The conjugate acid of the acetate anion is acetic acid, $\text{CH"_3"COOH}$.