So you've got your sample in solution. What next? (W7)

Full text: Several factors must be considered after the sample is prepared for analysis. These factors include memory, oxidation state of analyte, presence of interfering elements, etc. Some elements are 'sticky' and exhibit prodigious memory effects. For elements like mercury, gold and boron, memory effects make it difficult to determine elemental concentrations in samples that vary widely in concentration. When selenium is determined by hydride generation, the selenium cannot be in the VI oxidation state, since borohydride will not reduce this oxidation state. Different treatments must be used. The treatment of organometallics may require, in addition, the presence of reagents to improve the yield of derivitized species that are to be determined. Interfering elements must sometimes be masked or removed before determination of the analyte can proceed. In this presentation, these various issues will be discussed. Solutions to some of the problems, from the analytical chemistry laboratories at Brock University, will be presented. In addition, options for the simultaneous determination of elements by vapor generation and nebulization will be discussed, based on recent work in the Brock laboratories. (author)