Question

For which of the following sparingly soluble salt the solubility (s) and solubility product `(K_(sp))` are related by the expression `s=(K_(sp)//4)^(1//3)`
A. `BaSO_(4)`
B. `Ca_(3)(PO_(4))_(2)`
C. `Hg_(2)Cl_(2)`
D. `Ag_(3)PO_(4)`

Answer 1

Correct Answer - C
`BaSO_(4) hArr Ba^(2+)+SO_(4)^(2-), `
`K_(sp)=s^(2)` or `s=[K_(sp)]^(1//2)`
`Ca_(3)(PO_(4))^(2) hArr 3Ca^(2+)+2PO_(4)^(3-),`
`K_(sp)=(3s)^(3) xx (2s)^(2)=108 s^(5) `or `s=(K_(sp)//108)^(1//5)`
`Hg_(2)Cl_(2) hArr Hg_(2)^(2+)+2Cl^(-),`
`K_(sp)=s(2s)^(2)` or `s=(K_(sp)//4)^(1//3)`
`Ag_(3)PO_(4)hArr 3Ag^(+) +PO_(4)^(3-),`
`K_(sp)=(3s)^(3)xx s =27s^(4)` or `s=(K_(sp)//27)^(1//4)`
`CuS hArr Cu^(2+)+S^(2-),`
`K_(sp)=s xx s=s^(2)` or `(K_(sp))^(1//2)`