Arsenic compounds sequential determination

The functions of the reagents used in the reduction of arsenic compounds, such as Zn, HCl, NiCla, SnCh, and KI are discussed below in connection with the Gutzeit method. Sodium borohydride also has been proposed as the reducing agent [39-42]. Sequential spectrophotometric determination of As(III) and As(V) is possible by using borohydride [40]. Hydrogen sulphide, which interferes in the reaction, is separated from arsine on cotton wool impregnated with lead acetate. 

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