Activity Coefficients of the System {yKCl + (1 – y)KH2PO4}(aq) at T = 298.15 K Determined by Cell Potential Measurements

• DOI: 10.1021/acs.jced.2c00704
• Publication Date: 2023-01-25T15:21:54Z
• Authors: Tijana Ivanović; Daniela Ž. Popović; Jelena Miladinović; Zoran P. Miladinović; Ferenc Pastor
• Keywords: Ternary numeral system; Scatchard plot

Zero-current cell potential measurements were used to determine the solution activity coefficient in a ternary system {yKCl + (1 – y) KH2PO4}(aq) at temperature T = 298.15 K. The of type K–ISE|KCl(mKCl), KH2PO4(mKH2PO4)|Ag|AgCl was total ionic strength range, Im 0.0886–1.0046 mol kg–1. In order generate set parameters that can be applied wide range mixed strengths, Pitzer, Scatchard, and Clegg–Pitzer–Brimblecombe models fit all available experimental data, including isopiestic from literature. calculated values thermodynamic properties for studied are excellent agreement. Potential interactions structure discussed by means excess free energy mixing via pairs, triplets, or quads investigated using Scatchard model parameters.