DIFFERENTIAL CAPACITANCE OF LIQUID LIQUID INTERFACES - EFFECT OF ELECTROLYTES PRESENT IN EACH PHASE/

The effect of electrolyte type and concentration on the differential c apacitance of the 1,2-dichloroethane/water interface has been measured . The results show that the differential capacitance is controlled by the pair ion (1)-counter-ion (2), where 1 and 2 denote the different p hases. At constant organic electrolyte composition the capacity increa ses in the order, 2-<HO-<ClO4-,Li+<H+<K+<Mg2+<Ba2+<Sr(2+)approximate t o Ca2+. By contrast, at positive potentials and constant aqueous elect rolyte composition, the capacitance decreases in the order, TPA(+)>MTM A(+)>TBA(+)>TOA(+),TPB->TCPB-. In very dilute solutions, the effects a re not noticeable.