Write the relatioship between `K_(sp)` and S of `BaSO_(4)` and AgCl.

Explanation

Both `BaSO_(4)` and AgCl belong to AB type of salts.
(a) Let the solubility of AgCl be S mol `dm^(-3)`
`AgCl_((s))hArrAg_((aq))^(+)+Cl_((aq))^(-)`
`[Ag^(+)]=S" mol "dm^(-3)and[Cl^(-)]=S" mol "dm^(-3)`
`thereforeK_(sp)=[Ag^(+)][Cl^(-)]=S*S=S^(2)`
(b) Let the solubility of `BaSO_(4)` be S mol `dm^(-3)`
`BaSO_(4(s))hArrBa_((aq))^(2+)+SO_(4(aq))^(2-)`
`[Ba^(2+)]=S" mol "dm^(-3)and[SO_(4)^(2-)]=S" mol "dm^(-3)`
`thereforeK_(sp)=[Ba^(2+)]*[SO_(4)^(2-)]=S*S=S^(2)`