Isopiestic investigation of the osmotic and activity coefficients of aqueous MgSO{sub 4} and the solubility of MgSO{sub 4}{center_dot}7H{sub 2}O(cr) at 298.15 K: Thermodynamic properties of the MgSO{sub 4} + H{sub 2}O system to 440 K

Journal Article · Tue Sep 01 00:00:00 EDT 1998 · Journal of Chemical and Engineering Data

DOI:https://doi.org/10.1021/je980047o· OSTI ID:659140

Archer, D G ^[1]; Rard, J A ^[2]

---

1. National Inst. of Standards and Technology, Gaithersburg, MD (United States). Physical and Chemical Properties Div.
2. Lawrence Livermore National Lab., CA (United States)

Isopiestic determinations of the osmotic coefficient of MgSO{sub 4}(aq) against NaCl(aq) and KCl(aq) reference standards were performed with long equilibration times ranging to 98 days. A value of the 298.15 K solubility of epsomite, MgSO{sub 4}{center_dot}7H{sub 2}O(cr), was also determined. The new measurements were combined with previous thermodynamic measurements to determine the thermodynamic properties of the MgSO{sub 4} + H{sub 2}O system from the ice-freezing line to 440 K. The thermodynamic measurements were fitted with two different models, an ion-interaction model and a chemical-equilibrium model. The ability of the two models to represent this system was examined.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 659140
• Journal Information: Journal of Chemical and Engineering Data, Vol. 43, Issue 5; Other Information: PBD: Sep-Oct 1998
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
54 ENVIRONMENTAL SCIENCES
MAGNESIUM SULFATES
HYDRATES
THERMODYNAMIC PROPERTIES
SOLUBILITY
EQUATIONS OF STATE
GROUND WATER
SURFACE WATERS