Question

At 25 °c, only 0.0100 mol of the generic salt ab2 is soluble in 1.00 l of water. what is the ksp of the salt at 25 °c? ab2(s)↽−−⇀a2+(aq)+2b−(aq)

Answer 1

Where the solubility product Ksp is applied where salts don't fully dissolve in a solvent.

and when the reaction equation is:

AB2(s) ↔ A2+(Aq)  + 2 B-(aq)

so we have the Ksp expression = [A2+][B-]^2

when we assume [A2+] = X = 0.01 M 


and [B-] = 2X = 2*0.01 M = 0.02 M

So by substitution:

Ksp = 0.01 * (0.02)^2

       = 4 x 10^-6