Data for Diffusion in Concentrated Solution of the System NaCl–KCl–H₂O at 25°: A Test of the Onsager Reciprocal Relation for this Composition

Abstract

The four diffusion coefficients which are necessary to describe the solute flows in a ternary solution have been measured for the system NaCl-KCl-HZ0 with each solute concentration equal to 1.5 molar. These data together with previously measured activity coefficients for this system are used to test the Onsager reciprocal relation for ternary diffusion. The Onsager relation is verified within 8%, and this value is less than the maxlmum expected error which is calculated from estimated individual errors in the various experimental data.

Ternary Solution Mutual Diffusion Coefficients and Densities of Aqueous Mixtures of NaCl and Na2SO4 at 298.15 K for Six Different Solute Fractions at a Total Molarity of 1.000 mol·dm-3

“…Mutual diffusion data are also available at 298.15 K for several common-anion ternary aqueous solution compositions relevant to natural waters. These are mostly chloride salt mixtures (Albright et al, 1989;Dunlop, 1959;Dunlop and Gosting, 1959;Kim, 1982;Leaist, 1988;Mathew et al, , 1990Miller et al, , 1993Miller et al, , 1996O'Donnell and Gosting, 1959;Paduano et al, 1989;Rard andMiller, 1987, 1988), as well as one composition of the system NaHCO 3 + KHCO 3 + H 2 O (Albright et al, 1987). Noncommon ion mixtures of NaCl + MgSO 4 + H 2 O have also been studied (Hao and Leaist, 1995).…”

An eigenvalue method for determination of multicomponent diffusion coefficients. Application to NaOH + NaCl + H2O mixtures

“…Let Y represent the refractive index (4)(5)(6)(8)(9)(10)(11)(12)(13), conductance (1 4 , 2 I), density (26), optical absorbance (27), or another concentration-dependent property measured along the path of diffusion during an experiment. For initial concentration differences Aci(0) across a sharp diffusion boundary, the corresponding difference in Y is " n [7] …”

“…In many cases the diffusivity of a solute in a multicomponent mixture is significantly different from its binary diffusivity, especially if the solutes are electrolytes or they react chemically (3)(4)(5)(6)(7)(8). Moreover, because diffusional flows interact, multicornponent diffusion of a component produces countercurrent or cocurrent flows of other components in the mixture.…”

Diffusion in Multicomponent Aqueous Systems

“…In Table I are the calculated values of the L-coefficients of the system H z O -N~C~-K C~ a t 25 "C using both approximations [13] and [I41 with eq. [9], [GI, [lo], and [12]. The values calculated by the method given in 11, and by Wendt (7), are also included, together with the experimental values of Dunlop and Gosting (8) and Dunlop (9).…”

“…[9], [7], [lo], and [12], are summarized in Table 111. The ratios of H+/HS04-concentrations were calculated by a method given by Baes (13), and with the assumption that the NaSOi-concentration was zero, except for the last column of Table 111.…”