Determination of Bismuth with p-Acetylarsenazo by Spectrophotometry

In 0.090 mol/L of nitric acid medium, p-acetylarsenazo and bismuth(III) form a 2:1 purple red complex. Its maximum absorption wavelength is located at 666 nm and the apparent molar absorptivity is epsilon(666nm) = 4.46 x 10(4) L mol(-1) cm(-1). When the content of bismuth(III) is in the range of 0.50-4.5 mu g/mL. The detection limit of the method is 0.13 mu g/mL. The method has been successfully applied to the determination of bismuth in water sample.