Molecular-emission spectroscopy in cool flames. Part IV. The determination of chloride, bromide and iodide by thermal-emission spectroscopy in the presence of indium salts

Abstract

A sensitive and selective molecular-emission method for the determination of chloride, bromide and iodide is described, involving measurement of the intense InCl, InBr and InI band-emission signals. A cool nitrogen-hydrogen diffusion flame is used and measurements are made at 360, 376 and 410 nm, respectively. Chloride can be determined in the presence of a large excess of bromide and iodide, bromide in the presence of a large excess of chloride and iodide, and iodide in the presence of a large excess of chloride. The use of other flame types and the gallium halide system are also described.