Calculate the maximum concentration (in m) of silver ions (ag+) in a solution that contains 0.025 m of co32-. the ksp of ag2co3 is 8.1 x 10-12.

Equilibrium equation is

Ag2CO3(s) <---> 2 Ag+(aq) + CO32-(aq) 

From the reaction equation above, the formula for Ksp: 

Ksp = [Ag+]^2 [CO32-] = 8.1 x 10^-12 
You know  [CO32-], so you can solve for [Ag+] as: 
(8.1 x 10^-12) = [Ag+]^2 (0.025) 
[Ag+]^2 = 3.24 x 10^-10 
[Ag+] = 1.8 x 10^-5 M