Standard State Thermodynamic Properties of Aqueous Sodium Chloride Using High Dilution Calorimetry at Extreme Temperatures and Pressures

Abstract

In this communication, we report the first calorimetric data for the standard state enthalpies of a solution of sodium chloride obtained from high dilution, down to (10(-3) m), integral heats of solution measurements to 596.30 K. Although there are no comparable thermodynamic data available at such high dilutions in the literature, the present results for NaCl(aq) can be used for many thermodynamic studies by others to achieve a complete thermodynamic description of this key electrolyte over very wide ranges of concentration. From the recently developed unified theory of electrolytes, the experimental data from this study were used to predict Gibbs free energies of hydration of sodium chloride up to 1100 K. These Gibbs free energies of hydration at different pressures and densities compare well with reported values obtained from ab initio calculations by others.

Standard state thermodynamic properties of aqueous sodium perrhenate using high dilution calorimetry up to 598.15K

“…15 The resulting standard state partial molar heat capacities of NaReO 4 (aq) calculated from equation (11) and the parameters from table 3 are given in table 5: TABLE 3 Empirical parameters used to calculate the standard state enthalpies of solution at p sat from equation (8). a 1 À1.07518E+04 a 2 1.97861E+00 a 3 À1.98703EÀ03 a 4 À7.96380EÀ01 a 5 6.52909E+02 a 6 1.01097E+04 a 7 3.74633E+00…”

“…Therefore, parameters for the temperature dependence of partial molar heat capacities, C p;2 , of NaClO 4 (aq) can be used in estimating other thermodynamic properties for NaTcO 4 (aq), for example, the calculation of the temperature dependence of the equilibrium constant of the disproportionation and solubility reactions of hydrated TcO 2 (cr) [9][10][11] and reduction of TcO À 4 ðaqÞ by Fe 2+ (aq) [21,22]. The standard state partial molar heat capacities of NaReO 4 (aq) from present study and those of NaCl(aq) [5] are compared in figure 5. The general behavior of C p;2 with the temperatures is similar for the two electrolytes that differ only in the nature of the two anions.…”

“…The standard state thermodynamic properties of NaReO 4 (aq) and NaCl(aq) [5] allow quantitative comparison between these two electrolytes that differ only in the nature of the two anions. These data will also provide the bases to convert studies on transition metal perrhenates [6] to that of the corresponding chlorides which are simpler to treat theoretically.…”

“…There is also one extremely important application of the data from sodium perrhenate solutions. The thermodynamic properties of NaCl(aq) [5], HReO 4 (aq) [7], and NaReO 4 (aq) from present study can be combined by ionic additivity to obtain data on the very important species, HCl(aq).…”

Phenomenon of Motion of Salt along the Walls of the Container

“…These have been well studied historically over the past century (Djamali and Cobble, 2009), (Hargreaves, et al, 2010), (Ho, et al, 1994), (Nielsen, et al, 1952), (Noyes and Falk, 1912), (Ozbek and Phillips, 1980), (Ramires, et al, 1994), (Smith Jr. and Dismukes, 1964), (Truesdell, 1968), (Uchida and Matsuoka, 2004), (Wadsworth, 2012), (Winsor and Cole, 1985), (Khan, 2007a). Examples include investigations of an array of thermodynamic properties via a variety of experimental techniques.…”