What is the maximum concentration of Ni²⁺ that can be added to a 0.00700 M solution of Na₂CO₃ before a precipitate will form? (Ksp for NiCO₃ is 1.30 × 10⁻⁷)

Question

What is the maximum concentration of Ni²⁺ that can be added to a 0.00700 M solution of Na₂CO₃ before a precipitate will form? (Ksp for NiCO₃ is 1.30 × 10⁻⁷)

Answer 1

NiCO₃(s) <==> Ni²⁺(aq) + CO₃^2-(aq)

Ksp = [Ni²⁺][CO₃^2-]

1.30x10^-7 = [Ni²⁺][0.00700]

[Ni²⁺] = 1.86x10^-5 M