Question

What is the solubility product (or ion-product), Ksp, expression at equilibrium for calcium phosphate, Ca3(PO4)2?

Answer 1

Answer : The expression for solubility constant for this reaction will be,

$K_{sp}=[Ca^{2+}]^3[PO_4^{3-}]^2$

Explanation :

Solubility product : It is defined as the product of the concentration of the ions  that present in a solution raised to the power by its stoichiometric coefficient in a solution of a salt. This takes place at equilibrium only.

The solubility product constant is represented as, $K__{sp}$.

The dissociation of calcium phosphate is written as:

$Ca_3(PO_4)_2\rightleftharpoons 3Ca^{2+}+2PO_4^{3-}$

The expression for solubility constant for this reaction will be,

$K_{sp}=[Ca^{2+}]^3[PO_4^{3-}]^2$