In photography, solutions of sodium thiosulfate are used to dissolve unexposed AgBr (Ksp = 5.0 × 10-13) in the developing process for black-and-white film. What mass of AgBr can dissolve in 1.00 L of 0.238 M Na2S2O3?
Ag+ reacts with S2O32- to form a complex ion:
Ag+(aq) + 2S2O32-(aq) <--> Ag(S2O3)23-(aq) Kf = 2.9 × 1013