Basic flow of the testing program

Choose the electrolytes in solution and the activity coefficient method to be used. 

For a system containing two or more possible precipitates, calculate the invariant point(s), or mutual saturation pointfs) using the Newton-Raphson technique. 

Calculate the solubility of one electrolyte while varying the solution concentration of the other. This entails using the Newton-Raphson technique to solve the system model for the saturation concentrations at even increments of the solution concentration. For a solution of two or more possible precipitates, the points are found between the pure solution saturation pcnnt and the invariant point. For a solution of one possible precipitate, the pcnnts are found from the pure solution saturation point to a set maximum molality of the other electrolyte. 

For solutions containing three possible precipitates, the saturation molality of the third salt is found between the two invariant points. 

At the completion of these calculations, the program can either return to Step 1. or end. 

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