SPECTROPHOTOMETRIC DETERMINATION OF SCANDIUM BASED ON THE COCOLORATION EFFECT IN SCANDIUM-CERIUM-P-ACETYLCHLOROPHOSPHONAZO (CPAPA) SYSTEM

Scandium in the presence of cerium(III) forms, with p-acetylchlorophos phonazo (CPApA), a heteropolynuclei ternary beta-complex of scandium-c erium-CPApA. The complex gives a very sensitive reaction for scandium with a molar absorptivity of epsilon(Sc) = 2.29 x 10(5) l mol(-1) cm(- 1) due to the cocoloration effect. Most foreign ions can be tolerated in considerable amounts, The optimum conditions and the mechanism of t he complex formation reaction are discussed. A simple method is propos ed for the determination of scandium in alloys, with satisfactory resu lts.