THERMODYNAMIC ACTIVITY OF CALCIUM ION IN SODIUM CHLORIDE-CALCIUM CHLORIDE ELECTROLYTES

Experimental data on the mean activity coefficient of CaCl2 in NaCl-CaCl2 mixtures at ionic strengths below 1 m have been used to prepare a table of activity coefficients for Ca++ in solutions of physiological interest. The establishment of an empirical calcium ion activity scale is discussed, and a number of possible assumptions are examined. The assumption γ++ = (γ±)2 is suggested as being the simplest with a theoretical basis. © 1968, The Biophysical Society. All rights reserved.