Question

If the solubility of `CaSO_(4)` in `H_(2)O` is `10^(-5)M`, Calculate the solubility in `0.005M` solution of `H_(2)SO_(4)`.

Answer 1

Correct Answer - A::B
`K_(sp) = [Ca^(2+] [SO_(4)^(2-)]`
`=10^(-5) xx 10^(-5) = 10^(-10)M^(2)`
Solubility in `0.005 M H_(2)SO_(4)`:
`{:(H_(2)SO_(4)rarr,2H^(o+)+,SO_(4)^(2-),,),(0.005,0,0,,),(0,0.005xx2,0.005,,):}`
Due to common ion effect `(SO_(4)^(2-))`, the wsolubility of `CaSO_(4)` is supressed.
`S_("new") = (K_(sp))/((C)^(n)) = (10^(-10))/((0.005)^(1)) = 2 xx 10^(-8)M`