The polarography of some oxonium ions in methylene chloride. Part I. Experimental techniques and results for two tertiary ions

Abstract

The techniques used for the first polarographic measurements on oxonium ions in methylene chloride in the presence of tetra-n-butylammonium tetrafluoroborate supporting electrolyte are described. A three electrode polarographic cell was used with a dropping mercury working electrode, platinum counter-electrode, and silver iodide in methylene chloride reference electrode. The triethyl-and the ethyl(tetramethylene)-oxonium ions are reduced in a one-electron, irreversible step at half-wave potentials of –0.33 and –0.30V, respectively. As the diffusion current is proportional to the concentration of the oxonium ion, polarography can be used to assay tertiary oxonium ions down to 10^–4M.