Theory of Electrolysis at Constant Current in Unstirred Solution - 2 - CONSECUTIVE ELECTROCHEMICAL REACTIONS
Abstract
Rigorous mathematical analyses are presented for 3 types of electrode processes in electrolysis at a constant current in unstirred solution: (1) the cathodic process followed by reoxidation resulting from current reversal; (2) reduction of a 2-component system; and (3) stepwise reduction of a single substance. The concentrations of the substances were derived by utilizing Fourier and Laplace integral tranforms; the corresponding transition times (tau) were calculated. Equations were derived for the potential-time curves of processes 1 and 3. In the first process, the tau for the reoxidation process was 1/3 the tau for the preceding cathodic process. The potential-time curve provided a means of studying the kinetics of electrode processes involving cathodic and anodic overvoltages exceeding 0.1 v by yielding the rate constant at zero potential, the transfer coefficient, the activation free energies for the forward and backward electrochemical reaction, and the standard potential for the couple. For process 2, the tau was more difficult to reduce; tau was a function of the bulk concentration of the substance and the concentration of the substance being reduced at less cathodic potentials. Quantitative relationships between the tau's for the 2 steps were derived. For process 3, the ratio of tau's was not proportional to the ratio of the number of electrons involved in the corresponding electrode processes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1953
- Accession Number
- AD0013647
Entities
People
- Paul Delahay
- Talivaldis Berzins
Organizations
- Louisiana State University