Answer:
[[tex]SO_4^{-2}[/tex] ]minimum=1.42*[tex]10^{-3}[/tex]M
Explanation:
Precipitate occurs only when the ionic product is greater than the solubility product.
I.e. Kip>Ksp
And from above equation it is clearly that the minimum value of Kip is equal to Ksp
[tex]CaSO_4[/tex] (aq) = [tex]Ca^{+2}[/tex] (aq)+[tex]SO^{-2}[/tex] (aq);
Ksp=[[tex]Ca^{+2}[/tex]][[tex]SO_4^{-2}[/tex]];
Hence Kip=Ksp; minimum value of Kip is equal to Ksp and this will give the minimum concentration of SO4-2 to precipitate the 0.050 M solution of Ca2+
Kip = [[tex]Ca^{+2}[/tex]][[tex]SO_4^{-2}[/tex]] = Ksp=7.10 × 10-5
[[tex]SO_4^{-2}[/tex]] =Ksp/[[tex]Ca^{+2}[/tex]] ;
[[tex]SO_4^{-2}[/tex]]=(7.10 × 10-5)/0.050;
[[tex]SO_4^{-2}[/tex]]minimum=1.42*[tex]10^{-3}[/tex] M
