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It is shown that the assumption of Kamieński that the water/air potential difference χH2Ois a quantity of the order of 1 V, must be rejected, as leading to impossible values for the chemical hydration energies of univalent ions.

Applications of a potentiostatic anodic step charging method (described in the following paper) have been made to the study of the involvement of surface oxide species in the oxygenevolution reaction at nickel electrodes in alkaline solution. The potential range covered included a region where faradaic oxygen evolution can occur. Under these conditions, a method based on principles described in the following paper must be adopted, since currents of both a faradaic (for the over-all reaction) and a pseudo-faradaic (for the surface charging process) origin pass in a common range of potentials. The potential-sweep method under these conditions yields results that are difficult to interpret. Comparison of the result obtained with those from the latter method and from the galvanostatic reduction method is made over appropriate ranges of potential. The formation of various oxide species at the electrode surface is indicated by studies on the stoichiometry of the oxide, as determined by chemical methods. The surface oxide formation or reduction charges are found to be logarithmic well potential up to and well beyond apparent monolayer coverage.

This paper considers some electrochemistry and the electrochemical engineering principles for design and optimization of fuel cells.

It has been a general belief that manganese dioxide for dry cell use should be as pure as possible and particularly free from heavy metal impurities, especially lead. This paper examines the effect of lead contained in manganese dioxide upon the self-discharge of dry cell.

The paper describes a study of stress corrosion in brass (62·8 per cent Cu, 37·2 per cent Zn) exposed to ammoniacal copper sulphate solution. The relation between the stress corrosion behaviour and the composition of the corrosive medium is discussed against the background of potential/ pH diagrams for the corroding system.

This paper considers the problem of the kinetics of adsorption at the electrode/solution interphase, for a substance which does not undergo chemical or electrochemical reactions. The differential system which describes semi-infinite linear diffusion to a plane has been examined, assuming that at the boundary a generic isotherm holds. In this way one arrives at a Volterra integral equation which in general is non-linear. The numerical solution of such an equation has been carried out for the case of a Frumkin isotherm. The coverage of the electrode‡ μ = Γ/Γmas a function of the adimensional quantity log z[= log (C*24Dt/Γm2π)] depends on the parameters βC* = Ψ and Aof the isotherm. The relative graphs allow us to determine the time required to arrive at a fixed coverage. The effects of attractive and repulsive interactions are discussed.

A method for calculating the charge associated with deposition of adsorbed intermediates at an electrode surface is derived kinetically for the case of current/time transients arising from a potential step when the steady-state rate of the over-all process is changed as well as the coverage by species involved in that process. As an example, two previously proposed mechanism for oxygen evolution at an anode surface are considered. The method has been applied experimentally in the preceding paper in this series to the determination of charge and hence pseudocapacitance associated with surface species arising in the oxygen-evolution reaction at nickel electrodes under various conditions. The method is also applicable to determinations of charge associated with adsorbed H in the hydrogen-evolution reaction at cathodes.

The topics treated in this paper concern: potential gradients and ionic migration in transference cells containing single or multiple electrolytes of any valency type; cells containing two identical working electrodes and single ion-permeable membrane; and the four-membrane osmionic cell. Osmionic demineralization is then developed from the theoretical analysis as a practical problem.

The two-year period, 1963 and 1964, was a banner one for fuel-cell patents; about six dozen patents were issued in the United States. This review paper discusses these patents under the following seven headings: (1) electrodes, (2) fuel-cell systems, (3) electrolytes, (4) regenerative fuel cells, (5) liquid-fuel fuel cells, (6) controls for fuel cells, and (7) devices that use fuel cells. Several technologically important or historically interesting patents were granted and include the Shell electrode (which was used in the construction of a 5-KW reformed methanol system) and the sodium-amalgam battery of Yeager.

Generally, an electrode process is assumed to behave as a linear element at potential departures from equilibrium not exceeding 5 mV. In this paper a rigorous examination is presented of the maximum overpotential at which linearization of the i/Erelationship for charge-transfer and mass-transfer controlled electrode processes is allowed. It appears that the 5-mV limit is an over-estimate. Mostly the excursion from equilibrium potential should not exceed 0.5 mV.