Abstract: | The metal chelates of Zr(IV) and Th(IV) with aspartic and glutamic acids have been studied potentiometrically. Stepwise stability constants in 0.1 M sodium perchlorate at 25 degrees are reported as: aspartate chelates-log K(1) 9.70, log K(2) 6.85, and log K(3) 3.50 for Zr, and log k(1) 9.23, log K(2) 8.57, log K(3) 4.55 and log K(4) 3.87 for Th; glutamate chelates-log K(1) 9.60, log K(2) 6.40 and log K(3) 3.32 for Zr and log K(1) 9.11, log K(2) 8.52, log K(3) 4.18 and log K(4) 3.62 for Th. |