Chapter 6, Problem 6E.14E

Interpretation Introduction

Interpretation:

The molar concentrations of $H_{2}S,H{S}^{-},and{S}^{2-}$ present in the final solution of $0.250M{H}_{2}S\left(aq\right)$ at $pH$ of $9.35$ have to be calculated.

Concept Introduction:

Fractions of species in a solution of diprotic acid $\left(H_{2}A\right)$ can be calculated as given below.

  $\begin{array}{l}f\left(H_{2}A\right)=\frac{{\left[H_3{O}^{+}\right]}^2}{H}\\ \\ f\left(H{A}^{-}\right)=\frac{\left[H_3{O}^{+}\right]K_{a1}}{H}\\ \\ f\left(A^{2-}\right)=\frac{\left[H_3{O}^{+}\right]K_{a1}{K}_{a2}}{H}\\ \\ Where,H={\left[H_3{O}^{+}\right]}^2+\left[H_3{O}^{+}\right]K_{a1}+K_{a1}{K}_{a2}\end{array}$