Polarography of the hydrogen ion in aqueous solutions of some tetraalkyl ammonium bromides

Abstract

The mobility and mode of reduction of the hydrogen ion is measured polarographically in aqueous solutions of some tetra-alkyl ammonium bromides, where the alkyl group is methyl, ethyl, propyl, and butyl. The results are compared with those for alkali-metal halides. It appears that the two classes of salts operate by different mechanisms in reducing the mobility of the hydrogen ion and modifying the potential at which it is reduced. The presence of the alkyl group rather than the charge density appears to be the reason for the low mobility and the decrease in the ease of reduction of the hydrogen ion. The formula of the hydrogen ion in aqueous solutions of tetra-propyl and -butyl ammonium bromides seems to be H₉O₄⁺, as compared with H₃O⁺ in 13M-lithium chloride.