The Stabilities of Secondary Tin Minerals. Part 2*: The Hydrolysis of Tin(II) Sulphate and the Stability of Sn3O(OH)2SO4

R. Edwards, R. D. Gillard and P. A. Williams
School of Chemical and Physical Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
Department of Chemistry, University of Wales, Cardiff, P.O.Box 912, Cardiff CF1 3TB, UK
School of Chemistry, University of Western Sydney, Nepean, P.O.Box 10, Kingswood, NSW 2750, Australia
*Part 1: Edwards, R., Gillard, R.D. and Williams, P.A. (1992) Mineral. Mag., 56, 221-6.

Abstract: Tritin(II)dihydroxyoxosulphate, Sn3O(OH)2SO4, is a rare corrosion product found on the surfaces of certain tin alloys. A new synthesis based on the hydrolysis of SnSO4 is described. The stability constant determination of Sn3O(OH)2SO4,s, at 298.2K and 105Pa is determined using direct measurements via electrodes, of the activities of tin(II) and sulphate ions. ΔfG0(298.2K) is equal to −1563.1 ± 0.9 KJ mol−1.

Keywords: tin minerals • stability • tritin(II) dihydroxyoxosulphate

Mineralogical Magazine; June 1996 v. 60; no. 400; p. 427-432; DOI: 10.1180/minmag.1996.060.400.04
© 1996, The Mineralogical Society
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