Dissociation Constants and Dissociation Velocities of Substituted Pyruvic Acids

Abstract

IT has been shown¹ that weak acids are very often reduced polarographically in two steps. The more positive step belongs to the undissociated acid, the more negative to the acid ion. The total height of these two steps remains constant; but their ratio is changed in a characteristic way with the pH of the solution. If we plot this ratio against the pH, we obtain a curve which resembles very closely a dissociation curve. The pK of this dissociation curve is, however, generally shifted several pH units to higher values in comparison with the true acidity of the particular acid.