The Pitzer equations have been shown to be very useful in estimating the physical chemical properties of mixed electrolyte solutions like seawater. The equations account for all the ionic interactions occurring in a mixed electrolyte solution. In this paper, the Pitzer equations have been used to estimate the partial molar volumes of ions in 0.725 mol·kg-1 NaCl, which is a near equivalent for average seawater of absolute salinity S A = 35.165 g·kg-1. The calculated results at 25°C for a number of cations and anions are in good agreement with the measured values in 0.725 mol·kg-1 NaCl. The estimates in seawater are limited, due to the scarcity of volume data for metal sulfate and bicarbonate salts. The model can now be used to make reasonable estimates of the effect of pressure on equilibria in the oceans and other mixed electrolyte solutions over a wide range of composition, at 25°C, and for some of the major sea salts and the rare earth cations from 0 to 100°C.
- Partial molar volumes
- Pitzer equations
ASJC Scopus subject areas
- Molecular Biology
- Physical and Theoretical Chemistry