Abstract
A new colorimetric method for the determination of micro quantities of sulfate using barium complex of dihydroxytoluquinone (DHTQ-Ba) has been investigated. DHTQ-Ba reacts with sulfate in an alcoholic solution to give a red-violet coloration corresponding to the amount of sulfate. The colored solution containing DHTQ anion is very stable. The absorbance measured at 515 mμ against the reagent blank obeys Beer's law up to 70 μg/ml of sulfate. The effect of foreign ions and the elimination of interfering ions are also discussed.
