Question

The solubility product of PbS in 4.2 × 10^-28 at 300 K. The sulphide ions concentration required to precipitate PbS from a solution containing 0.001 M of lead ion is :

(a) ≥ 2.1 × 10^-14 mol/dm³

(b) ≥ 4.2 × 10^-14 mol/dm³

(c) ≥ 4.2 × 10^-25 mol/dm³

(d) ≤ 4.2 × 10^-28 mol/dm³

Answer 1

Option : (c) ≥ 4.2 × 10^-25 mol/dm³