Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Enthalpies of Solution of Sodium Chloride and Potassium Sulfate in Water. Thermodynamic Properties of the Potassium Sulfate and Water System

Published

Author(s)

Donald G. Archer, D R. Kirklin

Abstract

An adiabatic calorimeter was used to measure enthalpies of solution into water of sodium chloride (0.13 mol.kg-1) at nominal temperatures of 298.15 K, 303.15 K, and 308.15 K and of potassium sulfate (0.039 mol.kg-1) at nominal temperatures of 298.15 K and 303.15 K. The results for sodium chloride were compared to a previous equation of state so as to validate the use of values from that equation of state for calibration of, or checks on the accuracy of, solution calorimeters. 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) and 13 K to 854 K for K2SO4 (cr). New equations and/or values for the following properties are given in the present work: 1) thermal properties of K2SO4 (cr) from 0 K to near the orthorhombic to hexagonal transition at 857 K, 2) the change in chemical potential for both K2SO4 and H2O in K2SO4 (aq) as a function of temperature and molality, valid from 271 K to 500 K, 0 mol.kg-1 to the saturation molality, and to pressures of 40 MPa and 3) standard-state properties for the aqueous solution process.
Citation
Journal of Chemical and Engineering Data

Keywords

enthalpy of solution, potassium sulphate, sodium chloride, thermodynamic properties

Citation

Archer, D. and Kirklin, D. (2008), Enthalpies of Solution of Sodium Chloride and Potassium Sulfate in Water. Thermodynamic Properties of the Potassium Sulfate and Water System, Journal of Chemical and Engineering Data (Accessed May 25, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created October 16, 2008