Question

溶液中 zn+ cu+浓度为0.01,H+浓度0.3 通入硫化氢气体,已知CuS ZnS分别是6*10-36 2*10-

Answer 1

[S2-] = [H2S]*K1*K2 / [H+]^2 = 0.1*5.7*10-8*1.2*10-12 / 0.3^2

= 7.6*10-20

[Cu2+][S2-] = 0.1*7.6*10-20 > 6*10-36,有CuS沉淀.

[Zn2+][S2-] = 0.1*7.6*10-20 > 2*10-23,有ZnS沉淀.

CuS 沉淀先生成,ZnS沉淀后生成.