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Isopiestic Determination of the Osmotic and Activity Coefficients of K2SO4(aq) at the Temperatures 298.15 and 323.15 K, and Revision of the Thermodynamic Properties of the K2SO4 + H2O System
Published
Author(s)
D A. Palmer, Donald G. Archer, J A. Rard
Abstract
Isopiestic vapor-pressure measurements were made for K2SO4(aq) from 0.228 to 0.740 mol.kg-1 at 298.15 k and from 0.219 to 0.957 mol.kg-1 at 323.15 K, using NaCl(aq) as the isopiestic reference standard. These isopiestic measurements extend to saturation at 323.15 K and to slightly above saturation at 298.15 K. There are no previous isopiestic studies for K2SO4 (aq) at 323.15 K. Thermodynamic properties from the literature for the potassium sulfate + water system and the present measurements were used to generate equations that represented the thermodynamic properties of this system from the freezing point of the aqueous solution to 500 K. The measured values included in the fitted equations spanned the range of temperature of approximately 271 K to 530 K for K2SO4(aq).
Citation
Journal of Chemical and Engineering Data
Volume
47
Issue
No. 6
Pub Type
Journals
Keywords
Potassium sulfate, thermodynamic properties
Citation
Palmer, D.
, Archer, D.
and Rard, J.
(2002),
Isopiestic Determination of the Osmotic and Activity Coefficients of K<sub>2</sub>SO<sub>4</sub>(aq) at the Temperatures 298.15 and 323.15 K, and Revision of the Thermodynamic Properties of the K<sub>2</sub>SO<sub>4</sub> + H<sub>2</sub>O System, Journal of Chemical and Engineering Data
(Accessed October 27, 2025)