LANTANUM COMPLEXASI STUDY WITH MAKROSIKLIS COMPOUND AND CHARACTERIZATION AS SELECTIVE ELECTRONIC ION LANTANUM

Abstract

The aim of this research are (1) to study the complexation constant of La(III) ion by N,N’-dikarboksimetildiaza-18-crown-6 ligant with difference concentration of KNO3, and (2) to study the lanthanum (III) ion selective electrode (La-ISE) potential response which follows the Nernst equation. The characters of the electrode studied are: response time, life time, detection limit, dynamic range and selectivity. The complexation constant of La(III) ion by N,N’- dikarboksimetildiaza-18-crown-6 ligant are finded by potentiometry titration with 0.0005 M, 0.001 M, dan 0.005 M KNO3 supported electrolite. The titration are doing by 0.00794 M KOH until pH 7. The result of constant complexation (Kf) La(III) ion with N,N’-dikarboksimetildiaza-18-crown-6 difference KNO3 0.005 M, 0.001 M, dan 0.005 M simultaniuesly are 101,02 , 101,12, dan 101,32. The electrode had a response time of 27.14 ± 4.79 seconds and could be used for 50 days. The linear range was between 10-5 M to 10-1 M and the detection limit is 3.92x10-6 M.