Question

What is the maximum concentration of Ag⁺ that can be added to a 0.00250 M solution of Na₂CO₃ before a precipitate will form? (Ksp for Ag₂CO₃ is 8.10 × 10⁻¹²)

Answer 1

Concentration Na₂CO₃ = 0.00250 M

[CO₃^2-] = [Na₂CO₃] = 0.00250 M

K_sp Ag₂CO₃ = [Ag⁺]²[CO₃^2-]

8.10 x 10^-12 = [Ag⁺]² * (0.00250 M)

[Ag⁺]² = (8.10 x 10^-12) / (0.00250 M)

[Ag⁺]² = 3.24 x 10^-9 M²

[Ag⁺] = (3.24 x 10^-9 M²)^1/2

[Ag⁺] = 5.69 x 10^-5 M

Maximum concentration of Ag⁺ is 5.69 x 10^-5 M