Question

What is the concentration of Ag⁺ ions in 0.01 M AgNO₃ that is also 1.0 M NH₃ ? Will AgCl precipitate from a solution that is 0.01 M AgNO₃, 0.01 M NaCl and 1 M NH₃ ? 

K_d(Ag[NH₃]₂⁺) = 5.88 × 10^–8 ; 

K_sp(AgCl) = 1.8 × 10^–10

Answer 1

Let us first assume that 0.01 M AgNO₃ shall combine with 0.02 NH₃ to form 0.01 M Ag(NH₃)₂⁺ and the consider its dissociation.

Further, ionic product of AgCl = [Ag⁺ ] [Cl^– ] = (6.12 × 10^–10) (0.01) = 6.12 × 10^–12 

Because the ionic product is smaller than K_sp = 1.8 × 10^–10, no precipitate should form.