Answer:
Explanation has been given below.
Step-by-step explanation:
Let's consider solubility equilibrium of an ionic insoluble compound e.g.


Equilibrium constant of this solubility equilibrium is represented in terms of solubility product (
) which is expressed as-
![K_(sp)=[Ba^(2+)][SO_(4)^(2-)]](https://img.qammunity.org/2020/formulas/chemistry/college/eojmtmbkipv7xk5p0vd5tyqqx0mx01s29s.png)
Now, if we add an ionic salt e.g.
with a common ion
then concentration of
increases.
But, at a constant temperature,
is constant.
Therefore, to keep
constant, excess amount of
will combine with free
ion in solution and produce
.
Hence, as a whole, solubility of
decreases.