PRINCIPLES OF ELECTROCHEMISTRY

Three short articles providing a good understanding of important general principles of electrochemistry follow. 

J. Koryta and J. Dvorak, Principles of Electrochemistry,Wiley Sons, Inc., New York, 1987. 

Koryta, J., J. Dvofa k, and L. Kavan, Principles of Electrochemistry, Wiley, Chichester, West Sussex, England, 1993. 

The new edition of Principles of Electrochemistry has been considerably extended by a number of new sections, particularly dealing with electrochemical material science (ion and electron conducting polymers, chemically modified electrodes), photoelectrochemistry, stochastic processes, new aspects of ion transfer across biological membranes, biosensors, etc. In view of this extension of the book we asked Dr Ladislav Kavan (the author of the section on non-electrochemical methods in the first edition) to contribute as a co-author discussing many of these topics. On the other hand it has been necessary to become less concerned with some of the classical topics the details of which are of limited importance for the reader. 

A certain knowledge of the principles of electrochemistry is therefore of vital importance for the chromatographer who wants to achieve optimum HPLC-EC system performance. 

Electrochemical chemists, on the contrary, seem to be interested in the electrochemical processes as a means to verify the complicated formulae derived to describe these processes. Very little chromatographer-friendly literature is therefore available for the chromatographer who is forced to learn more about the principles of electrochemistry to be able to operate their HPLC-EC system properly. 

Koryta, J. (1993) Ions, electrodes and membranes, 2nd edition, Wiley-Liss Inc., USA Koryta, J., Dvorak, J. and Kavan, L. (1996) Principles of electrochemistry, John Wiley, UK. 

There are many publications which discuss not only the principles of electrochemistry, but also its practical aspects (electrodes, cells, solvents, supporting electrolytes, and so on).1-8 In addition, all the electrochemical instrumentation manufacturers have catalogues of commercial products which allow proper experiments to be carried out. Therefore, the present discussion will be limited to point out the minimal basic knowledge required to set up an electrochemical experiment. 

The principle of electrochemistry is to replace the direct electron transfer between atoms or molecules of a conventional redox reaction by separating... 

Koryta, J., Dvordk, J. and Kavan, L., Principles of Electrochemistry, 2nd Edn, Wiley, Chichester, 1993. The release of this second edition of a now-classic work was much welcomed. The text is well structured and always worth reading. Some of the examples are particularly relevant, although the voltammetric sections are inferior to those concentrating on potentiometric studies. 

J. Koi3fta, Principles of Electrochemistry, Wiley, New York, 1987 J. Goodisman, Electrochemistry Theoretical Foundations, Quantum and Statistical Mechanics, Thermodynamics, the Solid State, Wiley, New York, 1987 G. Battistuzzi, M. Bellei, and M. Sola, J. Biol. Inorganic Chem. 11, 586-592 (2006) R. Heyrovska, Electroanalysis, 18, 351-361 (2006) G. Battistuzzi, M. Borsari, G. W. Ranters, E. de Waal, A. Leonard , and M. Sola, Biochemistry 41, 14293-14298 (2002). 

Koryta, J. Dvorak, J. Principles of Electrochemistry, Wiley Sons, Chichester, England, 1987, pp. 367-369. 

Whenever you start a car, use a battery-powered device, apply a rust inhibitor to a piece of metal, or use bleach to whiten your clothes, you deal with some aspect of electrochemistry. Electrochemistry is that branch of science that involves the interaction of electrical energy and chemistry. Many of our daily activities use some form of electrochemistry. Just imagine how your life would be in a world without batteries. What immediately comes to mind is the loss of power for our portable electronic devices. While this would certainly be an inconvenience, consider the more critical needs of those with battery-powered wheelchairs, hearing aids, or heart pacemakers. In this chapter, we examine the basic principles of electrochemistry and some of their applications in our lives. 

The work of Davy was continued and expanded upon by the great English scientist Michael Faraday (1791-1867). Faraday s primary studies in electrochemistry took place between 1833 and 1836. Faraday is responsible for giving us much of our modern electrochemical terminology. The terms electrode, anode, cathode, electrolyte, anion, cation, and electrolysis are all attributed to Faraday. Even more important than his qualitative description of electrochemistry, Faraday did quantitative studies that led to his formulation of electrochemical laws. These laws provided a means to determine the relationship between current and the amount of materials reacting in an electrochemical reaction. Because Faraday s major contributions are still used today, they are covered in the principles of electrochemistry later in the chapter rather than in this historical section. 

The principles of electrochemistry that govern energy changes in the macroscopic circuit with a motor and battery apply with equal validity to the molecular processes accompanying electron flow in living cells. We turn now to a discussion of those principles. 

If you are not thoroughly familiar with the principles of electrochemistry, you should review Chapter 10 and the Latimer diagram derived there (below) before considering the following discussion for determining the stability of oxidation slates ... 

Electrochemistry finds wide application. In addition to industrial electrolytic processes, electroplating, and the manufacture and use of batteries already mentioned, the principles of electrochemistry are used in chemical analysis, e.g.. polarography, and electrometric or conductometric titrations in chemical synthesis, e.g., dyestuffs, fertilizers, plastics, insecticides in biolugy and medicine, e g., electrophoretic separation of proteins, membrane potentials in metallurgy, e.g.. corrosion prevention, eleclrorefining and in electricity, e.g., electrolytic rectifiers, electrolytic capacitors. 

PHYSICAL CHEMISTRY. Application of the concepts and laws of physics to chemical phenomena in order to describe in quantitative (mathematical) terms a vast amount of empirical (observational) information. A selection of only the most important concepts of physical chemistiy would include the electron wave equation and the quantum mechanical interpretation of atomic and molecular structure, the study of the subatomic fundamental particles of matter. Application of thermodynamics to heats of formation of compounds and the heats of chemical reaction, the theory of rate processes and chemical equilibria, orbital theory and chemical bonding. surface chemistry (including catalysis and finely divided particles) die principles of electrochemistry and ionization. Although physical chemistry is closely related to both inorganic and organic chemistry, it is considered a separate discipline. See also Inorganic Chemistry and Organic Chemistry. 

The goal of this volume is to provide (1) an introduction to the basic principles of electrochemistry (Chapter 1), potentiometry (Chapter 2), voltammetry (Chapter 3), and electrochemical titrations (Chapter 4) (2) a practical, up-to-date summary of indicator electrodes (Chapter 5), electrochemical cells and instrumentation (Chapter 6), and solvents and electrolytes (Chapter 7) and (3) illustrative examples of molecular characterization (via electrochemical measurements) of hydronium ion, Br0nsted acids, and H2 (Chapter 8) dioxygen species (02, OJ/HOO-, HOOH) and H20/H0 (Chapter 9) metals, metal compounds, and metal complexes (Chapter 10) nonmetals (Chapter 11) carbon compounds (Chapter 12) and organometallic compounds and metallopor-phyrins (Chapter 13). The later chapters contain specific characterizations of representative molecules within a class, which we hope will reduce the barriers of unfamiliarity and encourage the reader to make use of electrochemistry for related chemical systems. 

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