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Item Kinetics of Electrode Reactions in Liquid Ammonia: Part 4.—The Cun/Cu'/Cu° System in Acid Solution(Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (07), 1974) Brown, Oliver R.; Thornton, Sean A.The Cu^/Cu1 redox system is fully reversible on gold or platinum electrodes and quasi-reversible on vitreous carbon. When the metal electrodes are anodically oxidised prior to the measurements, the redox process is inhibited and curvature in the polarisation data indicate that the electrodes behave as p-type semi-conductors. The system Cui/Cu° possesses unusual features. Whereas the dissolu tion of Cu° to Cu1 is quasi reversible (Xr0 = 8xl0-5cms-1) the deposition reaction is severely inhibited by the formation of unidentified insulating films which also retard the reduction of Cu11 to Cu1. This result explains the poor quality of electrodeposits of copper from ammonia solutions described in the older literature.Item Kinetics of Electrode Reactions in Liquid Ammonia: Part 2.—FeIII/FeII and CoIII/CoII Redox Couples(Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Brown, Oliver R.; Thornton, Sean A.Polarisation data has been obtained for the CoH/CoHI and Fe'VFc111 couples at rotating disc electrodes of platinum, gold and vitreous carbon at -30°C in ammonia acid solution. In addition, metal wires and carbon rod have been used to examine the low level behaviour of the cobalt system and to record charge measurements in the oxidation of the anode surfaces. The iron couple is reversible on carbon but is inhibited by anodic films on gold and platinum. Apparent standard rate constants for the CoH/Co111 reaction are affected only slightly by the electrode material, but the oxidation branch is noticeably inhibited by anodic film formation. The mechanism of inhibition by anodic films is discussed. Fe111 is unstable in acid ammonia.Item Kinetics of Electrode Reactions in Liquid Ammonia: Part 3.—The Silver Electrode in Acid Solution(Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Brown, Oliver R.; Thornton, Sean A.The behaviour of the silver electrode in acid solutions of liquid ammonia has been studied by steady and non-steady state electrochemical measurements and electron microscopy. The apparent rate constant and standard potential have been determined. The rate-determining step in silver deposition and dissolution is the charge transfer reaction which is probably coupled with an adatom diffusion mechanism. Oxidised species originating from the solvent are adsorbed on silver except at cathodic values of electrode potential. The anodic behaviour of silver is complicated by the formation of anodic deposits, probably silver nitride, in parallel with the metal dissolution reaction. By making comparisons with silver electro-deposition from simple and cyanide aqueous baths it is concluded that the adsorbed solvent decomposition products are responsible for the poor quality of deposits from ammoniacal electrolytes.Item Kinetics of Electrode Reactions in Liquid Ammonia: Part 2.—FeIII/FeII and CoIII/CoII redox couples(Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (1-6), 1974) Brown, Oliver R.; Thornton, Sean A.Polarisation data has been obtained for the CoII/CoIII and FeII/FeIII couples at rotating disc electrodes of platinum, gold and vitreous carbon at – 30°C in ammonia acid solution. In addition, metal wires and carbon rod have been used to examine the low level behaviour of the cobalt system and to record charge measurements in the oxidation of the anode surfaces. The iron couple is reversible on carbon but is inhibited by anodic films on gold and platinum. Apparent standard rate constants for the CoII/CoIII reaction are affected only slightly by the electrode material, but the oxidation branch is noticeably inhibited by anodic film formation. The mechanism of inhibition by anodic films is discussed. FeIII is unstable in acid ammonia.