Spectrophotometric study of reactions in systems of rare earth (yttrium, scandium)-molybdenum(6)-arsenazo 3

Reactions in rare earths (Y, Sc)-Mo(6)-arsenazo 3 systems have been examined spectrophotometrically. Ternary different-metal complexes form which have absorption bands at 425, 575-579, 618-620, and 675-679 nm. The component ratio in the complexes of rare earths (Y, Sc):(Mo(6): arsenazo 3 is 1:1:1 at pH 3.6-4.0 for yttrium and 3.3-3.7 for scandium. Using the ability of molybdate ions to form heteropolycompounds involving elements other than rare earths and to form different-metal complexes involving rare earths (Y, Sc) methods have been developed of determining >= 0.001% for rare earths (Y, Sc) in reference samples, iron chromium, nickel, aluminium, beryllium, molybdenum and in their alloys. The analysis takes 1.5-2.5 hr depending on the alloy