No abstract

Metal-solution potentials of nickel in foreign ion solutions were investigated. It was found that nickel may show stationary potentials in potassium hydroxide and phosphate buffer solutions, if oxygen was excluded. The stable potentials were reversible with respect to a change of pH. It was noted that nickel was unable to displace hydrogen from a 0.1 M phosphoric acid solution; nickel dissolved only on admission of air. The possibilities of interpreting the observed potentials are discussed.

The preparation of solutions thought to contain simple aliphatic carbonium ions is described and their spectra recorded. Alternative explanations are considered, and the nature of the electronic transition is discussed.

Phase boundary potentials of nickel in various aqueous solutions, practically free from nickel ions, have been measured. The nickel-solution potentials in air drift and reach high positive (noble) potentials. The potentials of nickel vs. solution in an inert gas reach stationary values after several hours, depending upon the pH. The final potentials remain negative with respect to the standard hydrogen electrode. The differences of the corresponding potentials in the same solution, in presence of air and in absence of air, range up to half a volt or more. The role played by oxygen in influencing the potentials has an interesting bearing on the initial stages of the corrosion of nickel.