Chemical Thermodynamics of Tin - Volume 12 - OECD Nuclear ...

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IX Group 16 compounds and complexes
These values can be compared with calculated solubilities using the selected
and auxiliary standard formation data for solid phase, sulfur-containing species and
chlorido complexes of tin given in this volume Figure IX-4. The agreement with the
experimental data of Geyer and Mücke seems to be satisfactory and lends support to the
database established in this review. At concentrations of H + below 0.01 mol·kg –1 tin
speciation is dominated by hydroxido complexes and above this H + concentration
chlorido complex formation starts to dominate. The calculations of Kapustinskii do not
include hydrolysis. The virtual straight line, which can be drawn through the
experimental data of [1964GEY/MUC] and calculated points of [1940KAP] has to be
considered as accidental. Weigel [1907WEI] determined the dissolved ion
concentrations by measurement of the electrical conductivity assuming Sn 2+ and S 2– as
governing ions, which is not true (see Appendix A).
Figure IX-4: Solubility of SnS in aqueous HCl (: experimental data at 293 K
[1964GEY/MUC]; : calculated data [1940KAP]; : experimental data at 291 K
[1907WEI]; : calculated by this review).
-2
-3
log 10
(m(Sn)/mol·kg –1 )
-4
-5
-6
-7
-8
-9
1E-8 1E-7 1E-6 1E-5 1E-4 1E-3 0.01 0.1 1 10
m(HCl)/mol·kg –1 H 2
O
IX.1.1.3.2 Solubility of SnS 2 (cr)
Weigel determined the solubility of SnS 2 in water to be s = 1.13 × 10 –6 M at 271 K
using a commercial sample of “Musivgold” [1906WEI], [1907WEI]. Solubility data
published by Sorum and Wolf [1950SOR/WOL] are obviously too high (s = 10 –2 M at
CHEMICAL THERMODYNAMICS OF TIN, ISBN 978-92-64-99206-1, © OECD 2012