Solubility product constants, divalent

Table II. Solubility Product Constants for Divalent Metal Ion...

Equation 6.44 provides the temperature dependence of the solubility product constant for a solubilization reaction valid in a highly acidic region for divalent and quadrivalent oxides. 

Arnac, M., Verboan, G., "Solubility Product Constants of Some Divalent... 

The relative ability of the transition metal ions to form complex ions is Mn2+ < Fe2+ < Co2+ < Ni2+ < Cu2+ > Zn2+ for the divalent cations and Cr3+ — Mn3+ > Fe3+ < Co3+ for the trivalent cations. The strongest complexing divalent cation is Cu(II). Fe(III) is the weakest complexing trivalent transition metal ion, but is stronger than other trivalent cations such as Al3+ and the lanthanides. The heats of hydration (Table 3.2), strengths of EDTA complexes (Table 3.5), and solubility products of metal hydroxyoxides (Table 3.3) also follow this general order, with water, EDTA, and OH" as the respective ligands. Stability constants less than I09 indicate the weaker ion-ion interaction of ion pairs. 

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