State the meaning of partition coefficient.
The partition coefficient, $K_{pc}$, for butanoic acid between ethoxyethane and water equals $3.50$. A solution containing $2.00\,\text{g}$ of butanoic acid in $100\,\text{cm}^3$ ethoxyethane is mixed with water. The mixture is then left until the concentration of butanoic acid in each solvent no longer changes. The mass of butanoic acid present in the ethoxyethane layer is now $1.62\,\text{g}$. Calculate the volume of water used.
Define the term buffer solution.
Suggest one organic compound, and one inorganic compound, that could be added to two separate samples of aqueous butanoic acid to make buffer solutions.
Give the solubility product expression, $K_{sp}$, for aluminium hydroxide.
Calculate the numerical value of $K_{sp}$ for aluminium hydroxide. Include the units for $K_{sp}$ in your answer.