In terms of molar solubility, the Ksp Expression for the specified solid is Ksp = 4x3.
Ksp, which stands for solubility product constant, is the equation for the equilibrium dissolution of a solid.
The solid ab2 has now dissolved according to the formula;
a(aq) = ab2(s) + 2b (aq)
The equilibrium constant is therefore;
Ksp equals (a)(b)/(ab2)
Now, because the solids aren't included in the equation because there isn't enough concentration, it may be condensed to;
Ksp = [a][b]².
Now, molarity is also known as molar solubility, and as such, we shall say that x = a.
Due to the fact that b = 2x, there is twice as much b as there is a, therefore we may write a and b in
Ksp = [x][2x]
² = 4x³