Some photographic film is coated with crystals of AgBr suspended in gelatin. Some of the silver ions are reduced to silver metal on exposure to light. Unexposed AgBr is then dissolved with sodium thiosulfate in the “fixing” step.

(a) What is the equilibrium constant for this reaction?
(b) What mass of Na₂S₂O₃ must be added to dissolve 1.00 g of AgBr suspended in 1.00 L of water?

Transcribed Image Text:

AgBr(s) + 2 S,O32-(aq)= [Ag(S₂O3)21³(aq) + Br (aq)