Answer : The molar solubility of
in pure water is, 0.0118 M
Explanation : Given,

The solubility equilibrium reaction will be:

Let the molar solubility be 's'.
The expression for solubility constant for this reaction will be,
![K_(sp)=[Pb^(2+)][Br^(-)]^2](https://img.qammunity.org/2021/formulas/chemistry/high-school/9u9gisnnqfl1cjurzyxqlwpvh9hvlubrfd.png)

Now put all the given values in the above expression, we get:


Therefore, the molar solubility of
in pure water is, 0.0118 M