Extractive spectrophotometric determination of iron using 3-hydroxy-2-(2-thienyl)-4H-chromen-4-one

A highly sensitive method is described for the determination of iron(III). Iron(III) forms a brown coloured complex with 3-hydroxy-2-(2-thienyl)-4H-ch romen-4-one (HTC) in acidic medium which is conveniently extracted into chl oroform. The absorbance of the complex is measured at 415 nm. Beer's Law is obeyed up to 1.4 mug/ml with the molar absorptivity of 5.27 x 10(4) l/mol/ cm. The method is quite simple, sensitive and selective and has been employ ed for analyzing some synthetic samples, chemicals and brazing solder.