Determination of Ion Activity Coefficients from the Measurement of Membrane Concentration Potentials–Activity Behavior of Alkali-metal Cations in Aqueous Solutions at 25°C
暂无分享,去创建一个
The membrane concentration potentials across a permselective sulfonated polystyrene collodion-base membrane were measured with aqueous solutions of alkali-metal salts at 25.0°C. By assuming the ideal behavior of the membrane, the activity coefficients of the critical cations were determined from the membrane concentration potentials at ionic strengths higher than 0.01. The ion activity coefficients of alkali-metal cations were found to follow the order Li+>Na+>K+ for the chlorides, nitrates, perchlorates, and sulfates. The order of activity coefficients of Na+ in different halide solutions was bromide>chloride>fluoride. Considerable differences were observed between the individual and mean activity coefficients at ionic strengths higher than 0.01. The individual ion activity coefficients determined from the experimental data were analysed by means of the extended Debye-Huckel eauation.
[1] R. Neihof. The Preparation and Properties of Strong Acid Type Collodion-base Membranes , 1954 .
[2] K. Sollner. ION EXCHANGE MEMBRANES , 1953, Annals of the New York Academy of Sciences.
[3] R. Neihof,et al. Strong-acid type of permselective membrane. , 1951, Archives of biochemistry and biophysics.
[4] H. Gregor,et al. Improved methods of preparation of permselective collodion membranes combining extreme ionic selectivity with high permeability. , 1946, The Journal of physical chemistry.