Dissociation of weak acids during Gran plot free acidity titrations

Abstract
A comparison of weak and free acid concentrations measured by base titration and hydrogen ionactivities determined by direct pH measurement is described for several of our data sets for raincollected above and below a forest canopy in the eastern United States. These data illustrate theinfluence of weak acid dissociation during titration and the possible effect of activity coefficientson calculated free acid concentrations. DOI: 10.1111/j.1600-0889.1984.tb00240.x