Answer
Kps= 8.3568 x 10⁻⁹
Procedure
To calculate the Ksp, we will need the equation for the dissolving process so the equilibrium expression can be written. In this case, we have the following.
In₂(SO₄)₃(s) ==> 2 In³⁺(aq) + 3 SO₄²⁻(aq)
Once we have the equation, the Kps will be calculated as
Ksp = [In³⁺]²[SO₄²⁻]³
Where
[In³⁺] = 2 x 0.0095 M = 0.019 M
[SO₄²⁻] = 3 x 0.0095 M = 0.0285 M
Therefore Ksp= (0.019)²(0.0285)³=8.3568 x 10⁻⁹