Colour reaction of scandium with quercetin and its application to the analysis of scandium

A spectrophotometric study of the scandium-quercetin complex is described; μg amounts of scandium can be determined with quercetin at 43.5 mμ and pH 4.4. A 1:1 complex is formed. The apparent instability constant of the complex was estimated as 2.7·10^-7 by a spectrophotometric method. An ion-exchange method for separating scandium from several interfering ions is described.