Question

Estimate the mean ionic activity coefficient for CaCl2 in a solution that is 0.010 mol kg-1 CaCl2(aq) and 0.030 mol kg-1 NaF(aq).

Answer 1

The mean activity coefficient of the solution can be determined using the Debye Huckel limiting law as the concentration of the solution is very low. To calculate the coefficient, it is necessary to determine the ionic strength of the solution.

Then using the mean activity coefficient, we can calculate the mean ionic activity coefficient of Calcium chloride (a uni-bivalent salt) in a solution of Calcium chloride and Sodium Fluoride.

The steps of the calculation can be found in the image.

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