ION-EXCHANGE EQUILIBRIUM ON CARBOXYMETHYLDEXTRAN - THE SYSTEM NA-H+()

Titration data on carboxymethyldextran, CmDx, formerly treated by usin g the protonation reaction, are here treated by considering the ion ex change reaction. As expected the two approaches are equivalent, althou gh the former treatment allows direct comparison with protonation cons tants of the monomer in the literature. It is demonstrated that the pa rameters of one approach can be computed from the other. The ratios A !r/A!soln of the two components are also treated. They are sensitive to experimental errors and their use should be discouraged. Deviations from ideal behavior are accounted for by a simple three-parameter mod el.