State an expression for the solubility product, $K_{sp}$, of $\text{Ag}_2\text{S}(s)$.
The solubility of $\text{Ag}_2\text{S}(s)$ in water at $298\,\text{K}$ is $1.16 \times 10^{-17}\,\text{mol dm}^{-3}$. Calculate the numerical value of the solubility product, $K_{sp}$, of $\text{Ag}_2\text{S}(s)$ at $298\,\text{K}$.
Calculate the least volume of water needed to dissolve $1.00\,\text{g}$ of $\text{Ag}_2\text{S}(s)$ under standard conditions.
Bromic(I) acid, $\text{HOBr}(aq)$, is a weak acid, and its $K_a$ is $2.0 \times 10^{-9}\,\text{mol dm}^{-3}$. Calculate the pH of $0.20\,\text{mol dm}^{-3}$ $\text{HOBr}(aq)$.
$5.0\,\text{cm}^3$ of $0.20\,\text{mol dm}^{-3}$ potassium hydroxide, $\text{KOH}$, are mixed with $20.0\,\text{cm}^3$ of $0.20\,\text{mol dm}^{-3}$ $\text{HOBr}(aq)$. Calculate the pH of the buffer solution formed.