Rapid spectrophotometric determination of yttrium(III) with 4-(2-thiazolylazo)-resorcinol

Yttrium(III) reacts with 4-(2-thiazolylazo) resorcinol to yield a red-coloured 1:3 complex in the pH range 7.9-8.4. The complex is stable for 12 hr and exhibits maximum absorbance at 540 nm. Beer's law is obeyed over the concentration range 0.12-1.4 μg of yttrium/ml. The molar absorptivity and Sandell's sensitivity of the complex are 6.04 x 104 litre mol-1 cm-1 and 1.5ng cm-2 respectively. The interference of various diverse ions has also been studied. (author)