Spectrophotometric-isotope dilution determination of arsenic in soils and rock

F. W. Brown; F.O. Simon; L. P. Greenland

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Spectrophotometric-isotope dilution determination of arsenic in soils and rock

F. W. Brown·F.O. Simon·L. P. Greenland

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Abstract

Arsenic in soil and rock samples may be determined in part-per-million concentrations using a radiochemical-isotope dilution method. Arsenic in the sample plus added As 76 tracer is separated as arsine and determined spectrophotometrically as a molybdenum blue complex. The As 76 activity in the absorbing solution allows corrections for chemical losses. A lower limit of 1 ppm is determinate in a 0.5-g sample.

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F. W. Brown, F.O. Simon, L. P. Greenland. 1975. Spectrophotometric-isotope dilution determination of arsenic in soils and rock. https://pubs.usgs.gov/publication/70164422

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