Physical chemist Gibbs

Tbe angel is probably named after the great American physical chemist J. Willar Gibbs, who developed most of the theorems that permit the application of thermodynamics to interfaces. 

Physical chemists of the current generation can hardly imagine how atomic and molecular concepts were once doubted by serious scientists, even into the early 20th century Our current enlightenment reflects the debt that we owe to Boltzmann, Gibbs, Van der Waals, and other pioneer theorists. 

The electrical aspects of membrane phenomena have long been of interest in science, and attracted the attention in the nineteenth century of famous physical chemists including Gibbs, Nernst, Planck, and Ostwald. Originally, this interest was connected to electrical phenomena in biological systems. In the present discussion attention is focused on membranes used in specific ion electrodes. 

Entropy and the Third Law of Thermodynamics. It has been, for a long time, the ambition of physical chemists to compute Gibbs free energies from calorimetric data. This is due to the fact that direct free energy measurements are frequently difficult to carry out, whereas... 

The fact that a consistent thermodynamic theory which in detail can account for both adsorption and surface tension at planar surfaces has not yet been established has been regarded by many physical chemists as rather unsatisfactory. The theory of capillary formulated by Gibbs gives, owing to the use of excess functions, general relations of a limited practical value. Different readers have drawn controversial conclusions when studying... 

Nor was Ostwald the only one in the 1890s to recognize the worth of Gibbs. The Dutch physical chemist, Hendrik Willem Bakhuis Roozeboom (1854-1907), publicized Gibbs s phase rule throughout Europe and did so most effectively. 

Then, too, Gibbs s work was translated into French in 1899 by Henri Louis Le Chatelier (1850-1936). Le Chatelier, a physical chemist, is best known today for his enunciation of a rule, in 1888, that is still called Le Chatelier s principle. This rule may be stated Every change of one of the factors of an equilibrium brings about a rearrangement of the system in such a direction as to minimize the original change. 

This relationship was derived by the American physical chemist J. Willard Gibbs in the 1870s. 

This is the Nernst equation, after the physical chemist W. Nernst, who derived it at the end of the nineteenth century. As above, n is the number of electrons transferred in the cell reaction (2 in reaction 12.7), 5 the Faraday of charge, R the gas constant, and T the temperature (in kelvins). The constant 2.302 59 is used to convert from namral to base 10 logs. At 25 the quantity 2.30259 RT/3 has the value 0.05916, which is called the Nernst slope. The importance of (12.14) is that it allows calculation of the potentials of cells having nonstandard state concentrations (i.e., real cells) from tabulated values of standard half-cell values or tabulated standard Gibbs energies. 

We have two terms, AT x S and T x AS. We have to think a little bit about these two terms and use common sense (and a Httle bit of knowledge). The AT term is easy - the difference between two temperatures, Tj = 314.4 K and Ti = 309.8 K. But what is S It is the entropy content at temperature T, that is, a single-point value for the entropy function. Previously, on several occasions I said that in general you cannot know the entropy content (or the enthalpy content or the Gibbs energy content) at a single point only a difference between two points can be determined. And true to this statement most current physical chemistry textbooks will tell you that S is not defined, therefore G is not defined and you cannot calculate it this way. But physical chemists should know better read the following short note. 

Gibbs, Josiah Willard (1839-1903) American physical chemist whose theory of chemical thermodynamics became the foundation of physical chemistry. He also did pioneering work in statistical... 

J. Willard Gibbs, 1839-1903. Theoretical physicist and chemist, introduced the theory of thermod)Tiamics as key element into physical chemistry. He was appointed Professor of Mathematical Physics at Yale University in 1871. 

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