Chapter 18, Problem 102SAE

Interpretation Introduction

Interpretation:

Whether $\text{Al}{\left(\text{OH}\right)}_{\text{3}}$ precipitate from the given buffer solution or not needs to be explained.

Concept introduction:

For a buffer solution, the value of pH can be calculated using the Henderson-Hasselbalch equation as follows:

$pH=p{K}_a+\log \frac{\left[{\text{A}}^{-}\right]}{\left[\text{HA}\right]}$

Whether precipitate is formed or not can be determined by comparing the solubility product and reaction quotient.

If the value of $Q>K_{sp}$, $\text{Al}\left(\text{OH}\right)$ will precipitate and if $Q<K_{sp}$, there will be no precipitate.