Question $10$

For formic acid, $H\frac{C}{O}OH,K_a=1\mathrm{.}80{10}^{-4}mo\frac{l}{k}g$ in water at $25C$ and $\frac{1}{b}ar.($a$)$ For a solution of $4\mathrm{.}603g$ of $H\frac{C}{O}OH$ in $500\mathrm{.}0g$ of $H_{2}O$ at $25C$ and $\frac{1}{b}ar,$ find the $H^{+}$ molality as accurately as possible. $($b$)$ Repeat the calculation if $0\mathrm{.}1000$mol of $KCl$ is added to the solution of $($a$).($c$)$ Find the $H^{+}$molality in a solution at $25C$ and $1$ bar prepared by adding $0\mathrm{.}1000$mol of formic acid and $0\mathrm{.}2000$mol of potassium formate to $500\mathrm{.}0g$ of water.