Constantes de stabilité de thiocomplexes et produits de solubilité de sulfures de métaux. II Sulfure de zinc

Abstract

A mathematical treatment of solubility curves of sulfides is introduced for the determination of formation constants of complexes in solution. As an example, this theoretical method is used in the determination of the species in equilibrium in solution with a precipitate of zinc sulfide (β-ZnS). The excess of sulfide in solution varies from 0.0004 M to 0.01 M. The presence of Zn²⁺ is noted in acidic solution, followed by the presence of ZnS.H₂O or Zn(HS)(OH) for the rest of the pH scale. The solubility product of ZnS and the formation constant of Zn(HS)(OH) are given for an ionic strength 1.0 (NaClO₄) at 25 °C.