Thermodynamics of aqueous mixtures of sodium chloride, potassium chloride, sodium sulfate, and potassium sulfate at 25�C

Thermodynamic representation of the NaCl+Na2SO4+H2O system with electrolyte NRTL model

“…c Mean ionic activity coefficient of NaCl. Robinson et al[51] and Wu et al[52] reported osmotic coefficient data at 298.15 K with ionic strength at (1.08-9.43) molal. Marliacy et al[12] measured vapor pressure and molal dissolution enthalpies with temperature up to 363.15 K and molal ratio of NaCl to Na 2 SO 4 at 0.1, 1 and 10.…”

A General Method of Calculating the Water Activity of Supersaturated Aqueous Solutions from Ternary Data

“…The Zdanovskii Relation The prediction of the water activity, a,, of aqueous solutions is of both theoretical and practical interest (1,8). This is especially true of solutions of moderate to high concentrations.…”

Thermodynamic Properties of Aqueous-Mixed Electrolyte Solutions of {y Na2SO4 + (1 – y) K2SO4}(aq)

“…The thermodynamics of the Na 2 SO 4 –K 2 SO 4 (aq) system have been extensively characterized at a low concentration . In this study, the water activities for this system are performed at ionic-strength fractions y of Na 2 SO 4 ( y = I Na 2 SO 4 / I Na 2 SO 4 + I K 2 SO 4 ) of 0.2, 0.5, and 0.8 for total molalities between 0.2 mol·kg –1 and the saturation of one of the solutes at T = 298.15 K and P = 10 5 Pa.…”

“…The relative standard uncertainty of water activity is u ( a w ) = 0.0005 for a w > 0.95 and u ( a w ) = 0.002 for a w < 0.95, and for the osmotic coefficient ϕ is u (ϕ) = 0.006. b The reference water activity is 0.84; numbers in parentheses are for reference water activity of 0.98. Calculated form Pitzer mixing parameters given by Robinson, R. A. et al and Fillipov and Cheremnykh …”