STUDIES IN THE BEHAVIOUR OF BI-UNIVALENT SALTS IN AQUEOUS SOLUTION. PART III. LEAD ACETATE

Cells of the Hgx PbyI PbAc2 (C) HAc (cr) II salt bridge II Pb(NO3)2 (c) I Hgx Pby were studied earlier and the dissociation constant of PbAc+ \(\rightleftharpoons\) Pb+++ Ac- was shown to be 3.1 x 10-3. Study of cells of the type Hg ǀ Hg2 Ac2ǁ PbAc2 (c) HA (cr) ǁ Salt bridge ǁ NaAc (2c) HAc (cr) Hg2Ac2 ǀ Hg showed that lead acetate dissociated into two stages. By combining the results of the above two type of cell it was possible to calculate the two equilibrium constants. The value of k1 (\(PbAc_2 \rightleftharpoons PbAc^++Ac^-\)) was found to be 3.0 x 10-2 and that of k2 (\(PbAc^+\rightleftharpoons Pb^{++}+ Ac^-\)) to be 3.7 x 10-3. Study of the cells of the type in which there is no liquid junction potential Pbx Hgy ǀ PbAc2 (c) HAc (cr) Hg2Ac2ǀ Hg showed that the calculate values of k1 and k2 were correct and the salt bridges had been able to eliminate liquid junction potential effectively