Catalytic Spectrophotometric Determination of Trace Amounts of Manganese with Dibromxcarboxyarsenazo in Water

Decolourisation of dibromxcarboxyarsenazo by oxidation of hydrogen peroxide in ammonium muriatemedium using manganese as catalyst is investigated.λ_(max)=565 nm,the apparent molar absorption coeffi-cient is 2.6×10~4.L.mol~(-1).cm~(-1),the linear range for the determination of manganese is O～2.1μg/25mL.The method has been applied to the determination of trace amounts of manganese in water with satisfacto-ry results.