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Stability of hectorite in weakly acidic solutions. II. Studies of the chemical equilibrium and the calculation of free energy

Published online by Cambridge University Press:  09 July 2018

Kevin G. Tiller*
Affiliation:
Division of Soils, C.S.I.R.O., Adelaide, South Australia

Abstract

The chemical equilibrium of a purified sample of hectorite was studied over a range of pH, silicic acid, and magnesium chloride concentrations. The quasi-equilibrium reached by about 6 weeks was reversible with respect to added magnesium ions but only partially so for added silicic acid. The free energy of formation of hectorite at 25° C was calculated at −2680 kcal/unit cell, using the derived equilibrium constant and the stoichiometry of the reaction as previously established.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1968

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