Davies equation:

$log{}_{+-}=-0\mathrm{.}51z_{+}|z_{-}|[\frac{(I{)}^{\frac{1}{2}}}{1+(I{)}^{\frac{1}{2}}}-0\mathrm{.}30(I)]$

where $I=\frac{1}{2}{\displaystyle \underset{i}{\overset{?}{}}}{z}_i^2(\frac{b_i}{b^o})$ and $b$ represents molality and $z$ is the charge.

For $3-$hydroxypropionic acid, $K_a=3\mathrm{.}1{10}^{-5}$ at $25C.$

Estimate the molality of $H^{+}$in a $0\mathrm{.}120m$ solution of $3-$hydroxypropionic acid that also contains

$0\mathrm{.}100mNaN{O}_3$ at $25C.$ Use the Davies equation to estimate ionic activity coefficients. Neglect

ion pairing.

Estimate the molality of $H^{+}$in a buffer solution having $0\mathrm{.}12m3-$hydroxypropionic acid and

$0\mathrm{.}100m$ sodium $3-$hydroxypropionate at $25C.$ Use the Davies equation to estimate ionic activity

coefficients. Neglect ion pairing.