Determination of Germanium, Arsenic, Tin, Selenium, and Antimony by Plasma Emission Spectrometry with Hydride Generation and Chromatographic Separation

A semiautomated hydride generation device was coupled to a microwave-induced Ar/He plasma which is used with a 0.5 m monochromator. This coupling necessitated the use of a condensation tube and a Chromosorb 102 column to separate the analyte species from hydrogen produced during the generation reaction, and also to separate the analytes from condensed contaminants which cause spectral background interference. Data reported for Ge, As, Se, Sn, and Sb are detection limits in the ppb range and linear dynamic ranges which extend to 3 orders of magnitude. Precision of results ranges from 2.9 to 8.8%. Chromatographic characteristics of the elemental hydrides on 1, 3, and 6 ft columns are also reported. This system or portions of it can be used to substantially decrease both time and quantities of reagents needed for analysis in both simultaneous and sequential experiments in either emission spectroscopy or atomic absorption spectrometry.

Nuclear magnetic resonance study of electrolytes in 1,3-dimethylethyleneurea

A series of lithium, sodium, potassium, and ammonium salts were investigated by proton magnetic resonance spectroscopy in 1,3-dimethylethyleneurea, a relatively new non-aqueous solvent of high polarity and moderately high dielectric constant. The salts were found to shift the solvent proton peaks linearly as a function of salt concentration. Thiosulfate, perchlorate, and iodide salts shifted the solvent peaks downfield while tetraphenylborate salts uniquely shifted the peaks upfield indicating an unusual type of solvation behavior for the tetraphenylborates in this solvent.

Conductance and Conductometric Titrations of Picric Acid in Sulfolane at 30°

Conductance of picric acid solutions in sulfolane resembles the behavior seen in several other aprotic solvents and is suggestive of complex solution equilibria. The effect of water on equivalent conductance of picric acid is large for concentrations greater than about 0.3 M. Picric acid behaves as a weak acid in conductometric titrations.