What is the composition of the precipitate formed when H₂S gas is bubbled through 1.0 litre of a solution of 0.010 M Zn²⁺, 0.010 M Pb²⁺, and 0.010 M Mn²⁺, buffered at pH 2.0, until 0.10 mol of H2S has been added? [Ksp values are: ZnS: 1.6 × 10^-23; MnS: 7.0 × 10^-16; PbS: 7.0 × 10^-29. For H₂S, Ka1 = 1.0 × 10^-7; Ka₂ = 1.3 × 10^-13.

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The correct answer is E.The concentration of H2S in the solution is:[H2S] = 0.10 mol / 1.0 L = 0.10 MThe concentration of HS- in the solution is:[HS-] = [H2S] * Ka1 / [H+] = 0.10 M * 1.0 × 10-7 / 10-2 = 1.0 × 10-6 MThe concentration of S2- in the solution is:[S2-] = [H2S] * Ka1 * Ka2 / [H+]2 = 0.10 M * 1.0 × 10-7 * 1.3 × 10-13 / 10-4 = 1.3 × 10-16 MThe concentration of Zn2+ in the solution is:[Zn2+] = 0.010 MThe concentration of Pb2+ in the solution is:[Pb2+] = 0.010 MThe concentration of Mn2+ in the solution is:[Mn2+] = 0.010 MThe Qsp for ZnS is:Qsp = [Zn2+][S2-] = 1.0 × 10-6 M * 1.3 × 10-16 M = 1.3 × 10-22The Qsp for MnS is:Qsp = [Mn2+][S2-] = 1.0 × 10-6 M * 1.3 × 10-16 M = 1.3 × 10-22The Qsp for PbS is:Qsp = [Pb2+][S2-] = 1.0 × 10-6 M * 1.3 × 10-16 M = 1.3 × 10-22Since Qsp > Ksp for all three metal sulfides, all three metal sulfides will precipitate out of solution.

What Is the Composition of the Precipitate Formed When H2S

What Is the Composition of the Precipitate Formed When H₂S