Silver nitrate is slowly added to a solution that is 3.2 x 10^-3 M in Cl^- and 3.2 x 10^-3 M Br^-. Ksp(AgBr) = 5.0 x 10^-13 (assume the x-is-small approximation is valid for this calculation, then find some classmates and discuss: was it valid, how could you tell?)
a. What will precipitate first?
b. What percent of the first anion that precipitates will be left in solution when the second compound starts to precipitate?