The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform
Fritz Scholz - One of the best experts on this subject based on the ideXlab platform.
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Wilhelm Ostwald’s role in the genesis and evolution of the Nernst Equation
Journal of Solid State Electrochemistry, 2017Co-Authors: Fritz ScholzAbstract:The historical origin of the Nernst Equation can be traced back to Helmholtz’ treatment of the thermodynamics of galvanic cells and to Gibbs’ masterwork “On the Equilibrium of Heterogeneous Substances”. However, Nernst himself used a model of the metal/solution interface based on Arrhenius’ dissociation theory, together with some aspects of van’t Hoff’s osmotic pressure theory. Bancroft performed some initial studies of redox chains (cells) in Ostwald’s laboratory. Peters has advanced these studies and published an Equation correctly describing the potential of an inert electrode in a solution containing a dissolved reversible redox pair. Riesenfeld has treated interfaces of immiscible electrolyte solutions and the partition equilibria of ions. Luther has shown how standard potentials of elements possessing several redox states are related. Fredenhagen was the first to understand that the series of standard potentials are solvent dependent. Nernst, Bancroft, Peters, Luther and Fredenhagen were pupils of Ostwald; Riesenfeld and Fredenhagen were students of Nernst. Indeed, the presiding genius of the whole endeavour was clearly Friedrich Wilhelm Ostwald. This new survey of the genesis and evolution of what we now call Nernst Equation reveals the influence of Ostwald’s ideas on the theorizing process, and it is concluded that his share in the development of the modern theory deserves greater recognitions.
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wilhelm ostwald s role in the genesis and evolution of the Nernst Equation
Journal of Solid State Electrochemistry, 2017Co-Authors: Fritz ScholzAbstract:The historical origin of the Nernst Equation can be traced back to Helmholtz’ treatment of the thermodynamics of galvanic cells and to Gibbs’ masterwork “On the Equilibrium of Heterogeneous Substances”. However, Nernst himself used a model of the metal/solution interface based on Arrhenius’ dissociation theory, together with some aspects of van’t Hoff’s osmotic pressure theory. Bancroft performed some initial studies of redox chains (cells) in Ostwald’s laboratory. Peters has advanced these studies and published an Equation correctly describing the potential of an inert electrode in a solution containing a dissolved reversible redox pair. Riesenfeld has treated interfaces of immiscible electrolyte solutions and the partition equilibria of ions. Luther has shown how standard potentials of elements possessing several redox states are related. Fredenhagen was the first to understand that the series of standard potentials are solvent dependent. Nernst, Bancroft, Peters, Luther and Fredenhagen were pupils of Ostwald; Riesenfeld and Fredenhagen were students of Nernst. Indeed, the presiding genius of the whole endeavour was clearly Friedrich Wilhelm Ostwald. This new survey of the genesis and evolution of what we now call Nernst Equation reveals the influence of Ostwald’s ideas on the theorizing process, and it is concluded that his share in the development of the modern theory deserves greater recognitions.
A Aldaz - One of the best experts on this subject based on the ideXlab platform.
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do you really understand the electrochemical Nernst Equation
Electrocatalysis, 2013Co-Authors: Francisco J Vidaliglesias, Jose Sollagullon, Enrique Herrero, Antonio Rodes, A AldazAbstract:If you ask undergraduate students of Chemistry “Do you understand the electrochemical Nernst Equation [1]?”, a high percentage of them will answer “Of course, we do! It is the Equation that relates the activity of the species taking part in an electrochemical equilibrium to its electrode potential!” The next question: “So, would you be able to calculate how the electrode potential of the reaction Aþ Hþ þ e ! D ð1Þ
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understanding the Nernst Equation and other electrochemical concepts an easy experimental approach for students
Journal of Chemical Education, 2012Co-Authors: Francisco J Vidaliglesias, Jose Sollagullon, Enrique Herrero, Antonio Rodes, A AldazAbstract:The goal of the present laboratory experiment is to deepen the understanding of the Nernst Equation and some other concepts that are essential in electrochemistry. In this practical laboratory session, students first learn that the equilibrium potential of an electrode is related to the difference between two equilibrium inner electric potentials (also called Galvani potentials), namely, ϕM (inner electric potential of the metallic phase) and ϕsol (inner electric potential of the solution phase). Second, the concept of overvoltage is defined and the method to measure it is described. Finally, it is shown how and why the inner potential of a solution changes with the distance to the working electrode when a current flows through the solution and how the potential difference is distributed in an electrochemical cell when a current is flowing through it.
Charles R Martin - One of the best experts on this subject based on the ideXlab platform.
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rearranging the Nernst Equation to make a dosage controllable membrane delivery system
Journal of Electroanalytical Chemistry, 2017Co-Authors: Demetra M Pantelis, Juliette Experton, Charles R MartinAbstract:Abstract Electrochemically induced or augmented membrane-based drug delivery is a well-known art. However, it is often difficult to obtain a quantifiable relationship between quantity of drug delivered and voltage or current used. Described here is an alternative way of doing electrochemically induced membrane drug delivery where the membrane is smart and turns itself off when the desired amount of drug has been delivered. Furthermore, the amount of drug delivered at shut off is exactly quantifiable by a rearranged (exponential) form of the well-known Nernst concentration-cell Equation. We demonstrate this concept with a simple prototype system based on a commercial anion exchange membrane. For this system, the drug molecule must be an anion, and nitrate was used as the surrogate drug anion here.
K Itoh - One of the best experts on this subject based on the ideXlab platform.
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analyses of spectroelectrochemical behavior of polypyrrole films using the Nernst Equation monomer unit model and polaron bipolaron model
Journal of The Electrochemical Society, 1991Co-Authors: Takashi Amemiya, Kazuhito Hashimoto, Akira Fujishima, K ItohAbstract:A series of the absorption spectrum changes in polypyrrole films were analyzed using the Nernst Equation by two models. One is the "monomer unit model" and the other is the "polaron/bipolaron model." In the first model, formal electrode potentials and the n-values were obtained and usec~ to fit calculated hAbs vs. E curves to the experimental plots at three wavelengths. In the second model, the "apparent" excess chemical potentials were introduced to correct for the large deviations between the Nernst Equation and the Nernst plots obtained from the absorption spectra. The calculated hAbs vs. E curves were then fitted to the experimental plots. The "apparent" excess chemical potentials were assigned as corrections for species concentrations. Advantages of the monomer unit model over the polaron/bipolaron model are pointed out in the precise analyses of the spectroelectrochemical behavior of the films.
Francisco J Vidaliglesias - One of the best experts on this subject based on the ideXlab platform.
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do you really understand the electrochemical Nernst Equation
Electrocatalysis, 2013Co-Authors: Francisco J Vidaliglesias, Jose Sollagullon, Enrique Herrero, Antonio Rodes, A AldazAbstract:If you ask undergraduate students of Chemistry “Do you understand the electrochemical Nernst Equation [1]?”, a high percentage of them will answer “Of course, we do! It is the Equation that relates the activity of the species taking part in an electrochemical equilibrium to its electrode potential!” The next question: “So, would you be able to calculate how the electrode potential of the reaction Aþ Hþ þ e ! D ð1Þ
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understanding the Nernst Equation and other electrochemical concepts an easy experimental approach for students
Journal of Chemical Education, 2012Co-Authors: Francisco J Vidaliglesias, Jose Sollagullon, Enrique Herrero, Antonio Rodes, A AldazAbstract:The goal of the present laboratory experiment is to deepen the understanding of the Nernst Equation and some other concepts that are essential in electrochemistry. In this practical laboratory session, students first learn that the equilibrium potential of an electrode is related to the difference between two equilibrium inner electric potentials (also called Galvani potentials), namely, ϕM (inner electric potential of the metallic phase) and ϕsol (inner electric potential of the solution phase). Second, the concept of overvoltage is defined and the method to measure it is described. Finally, it is shown how and why the inner potential of a solution changes with the distance to the working electrode when a current flows through the solution and how the potential difference is distributed in an electrochemical cell when a current is flowing through it.