Judgment expressions for a moving chemical reaction boundary and isoelectric focusing

Judgment expressions for a moving or stationary chemical reaction boundary (MCRB, SCRB) and isoelectric focusing (IEF) are defined from the moving che mical reaction boundary equation (MCRBE). The judgment expressions are test ed with experiments cited in the literature and with those of a moving prec ipitate boundary formed by the reaction electrolytes CoCl2 and NaOH, couple d with the background electrolyte KCI. The judgment expressions are also us ed in comparisons between the transference numbers of the hydrogen ion in H Br, or HCl or HI solution with concentrations varying from infinite to 0.05 mol l(-1) and of the hydroxide ion in NaOH solution ranging from infinite concentration to 0.01 mol l(-1). The results show that predictions made wit h the judgment expressions are in agreement with experiment, that the judgm ent expressions are useful and convenient for judging the :movement of an M CRB and for comparisons of transference numbers of positive and negative re action ions such as hydrogen and hydroxide ions in IEF. In addition, the re sults also display the existence of the equal (or quasi-equal) transference numbers of hydrogen and hydroxide ions in Svensson's IEF..