ABSTRACT
This chapter describes some applications of the weak acids program, including calculations associated with titration curves and effects of buffer compositions on abilities of buffers to control the hydrogen ion concentration and pH. The chapter begins with a description of a program to plot titration curves as well as first and second derivatives of titration curves for up to six sets of conditions on each of three figures. Figures are included to illustrate effects of acid-base concentrations and deprotonation constants on shapes of titration curves. The programs include a feature that allows the user to superimpose transition ranges of indicators on titration curves. The chapter also describes programs used to quantify effects of buffer compositions on buffer performance. The discussion includes descriptions of buffer capacity, the conventional measure of buffer performance, as well as two new measures of performance called pH sensitivity and H+ sensitivity herein. Whereas buffer capacity depends indirectly on ratios of concentrations of acid-base pairs, both pH sensitivity and H+ sensitivity depend directly on these ratios.
