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

A Discussion of selected references
313
[1964GEY/MUC]
The solubility of SnS was determined by shaking about 0.6 g SnS in 300 mL of 0.1 M
and 1.0 M HCl solution under a CO 2 atmosphere in a closed glass vessel. After 4 h
(selected after testing time dependence of results) a solution sample was taken and
injected into 25 mL 20% HCl , which was boiled and purged with CO 2 before to remove
dissolved air. Then the acid solution was boiled under a CO 2 stream for 20 min to
remove H 2 S. Then the tin was determined iodometrically by the method of Höltje with a
0.01 M iodine solution.
SnS dissolves completely in 3 − 4 M HCl and 2 M NaOH. The results at 20 °C
are given in Table A-20.
Table A-20: Solubility of SnS in HCl at 20 °C.
[HCl]/M SnS SOL./mL Titrated 0.01 M I 2 /M Sn found/mg Solubility SnS/M
0.1 50 0.39 0.23 3.9 × 10 –5
0.1 50 0.40 0.24 4.0 × 10 –5
0.1 50 0.40 0.24 4.0 × 10 –5
1.0 20 1.09 0.647 2.7 × 10 –4
1.0 20 1.04 0.617 2.6 × 10 –4
1.0 20 0.95 0.563 2.4 × 10 –4
In parallel determinations the authors checked for absence of tin(IV) by
treating the solution with iron before titration.
No explicit information about temperature constancy is given, ΔT = ± 2 K
should be assumed.
Tin(II) sulfide used for the solubility experiments was carefully under
exclusion of air. Tin was dissolved in boiled HCl solution and SnS precipitated by
air-free H 2 S. Chemical analysis yielded an atomic ratio S/Sn = 1.000.
[1964YOU/GIL]
Several Pt-metal salts react with Sn(II) chloride leading to complex anions with
compositions of [RuCl 2 (SnCl 3 ) 2 ] 2– , [Rh 2 Cl 2 (SnCl 3 ) 4 ] 4– , [Ir 2 Cl 6 (SnCl 3 ) 4 ] 4– and cis/trans-
[PtCl 2 (SnCl 3 ) 2 ] 2– , where the trichlorostannate(II) ion is considered to be acting as an
anionic ligand with donor strength comparable to chloride ion. Neutral complexes of
Rh, Ir, and Pt were also prepared in which diolefin, triphenyl-phosphine/arsine ligands
are also coordinated to the metal ion beside a SnCl −
3
group (e.g. (C 7 H 8 ) 2 RhSnCl 3 and
(Ph 3 P) 2 PtCl(SnCl 3 )).
CHEMICAL THERMODYNAMICS OF TIN, ISBN 978-92-64-99206-1, © OECD 2012