Arsinates polarography

Methyl-bis(3-propyldimethylarsine)arsine (9) behaves almost as dpam No electrochemical oxidation is observed at Pt electrodes in 1 1 benzene/EtOH mixtures but in polarography at a Hg electrode a single oxidation wave with a maximum is observed at 0.01 V vs NHE. 

Of the diarylarsinic acids only the unsubstituted diphenylarsinic acid has been studied in detail by polarography in buffered aqueous solution" . The reduction is associated with adsorption as indicated by a prewave and a polarographic maximum on the main wave which, however, could be suppressed by addition of Triton X-100" . The height of the reduction wave is directly proportional to the concentration of Ph2 AsO(OH) in the range lO -lQ- M, and the limiting current (ij) is almost entirely diffusion-controlled". Similar conclusions were drawn for a series of bis(aminophenyl)arsinic acids based on measurements of ij as a function of the concentration and the height of the mercury column ... 

Gravimetric methods and chemical methods, such as colorimetric measurements based on the arsenic-molybdenum blue complex (1,2,3) and arsine generation in combination with silver diethyldithiocarbamate (4, 5, 6,7), have been used to measure arsenic in aqueous media. Various instrumental methods such as differential pulse polarography (8), heated vaporization atomic absorption (9), arsine generation in combination with atomic absorption spectroscopy (10, 11, 12) or non-dispersive atomic fluorescence spectroscopy (13), and optical emission spectroscopy (14) can be used to determine arsenic in aqueous solutions. 

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