Hildebrand, Joel

Heat of vaporization, 66 see also Vaporization Helium, 91 boiling point, 63 heat of vaporization, 105 interaction between atoms, 277 ionization energy, 268 molar volume, 60 on Sun, 447 source, 91 Hematite, 404 Hemin, structure of, 397 Hess s Law, 111 Heterogeneous, 70 systems and reaction rate, 126 n-Hexane properties, 341 Hibernation, 2 Hildebrand, Joel H.. 163 Holmium, properties, 412 Homogeneous, 70 systems and reaction rate, 126 Hydration, 313 Hydrazine, 46, 47, 231 Hydrides of third-row elements, 102 boiling point of. 315 Hydrocarbons, 340 unsaturated, 342... 

Hildebrand, Joel. (1891-1983). One of the most distinguished American chemists and teachers. Born in New Jersey, he obtained his doctorate in chemistry and physics from the University of Penn-... 

Hildebrand, Joel. Science in the Making, Columbia University Press, New York, 1957. 

Hildebrand, Joel H. (1958). Gilbert N. Lewis. Biographical Memoirs, National Academy of Sciences 31 209-235. 

Joel h. Hildebrand University of California Berkeley, California... 

Use of the potential of a galvanic cell to measure the concentration of an electroactive species developed later than a number of other electrochemical methods. In part this was because a rational relation between the electrode potential and the concentration of an electroactive species required the development of thermodynamics, and in particular its application to electrochemical phenomena. The work of J. Willard Gibbs1 in the 1870s provided the foundation for the Nemst equation.2 The latter provides a quantitative relationship between potential and the ratio of concentrations for a redox couple [ox l[red ), and is the basis for potentiometry and potentiometric titrations.3 The utility of potentiometric measurements for the characterization of ionic solutions was established with the invention of the glass electrode in 1909 for a selective potentiometric response to hydronium ion concentrations.4 Another milestone in the development of potentiometric measurements was the introduction of the hydrogen electrode for the measurement of hydronium ion concentrations 5 one of many important contributions by Professor Joel Hildebrand. Subsequent development of special glass formulations has made possible electrodes that are selective to different monovalent cations.6"8 The idea is so attractive that intense effort has led to the development of electrodes that are selective for many cations and anions, as well as several gas- and bioselective electrodes.9 The use of these electrodes and the potentiometric measurement of pH continue to be among the most important applications of electrochemistry. 

The regular solution model, introduced by the American UC Berkeley chemist Joel Henry Hildebrand (1881-1983) is the simplest way to consider these other contributions to the Gibbs energy (Hildebrand, 1929). In this case, Gex is of the form ... 

In the summer of 1914, his acceptance in hand and the 10 out-of-state tuition paid, Don arrived, via rail and steamship, in San Francisco to begin his college education at UC Berkeley. His freshman year was decisive by the summer recess he had found his calling through the inspired teaching of his chemistry professor, Joel Hildebrand and a young lab instructor Richard Tolman. 

I received a letter from Department Chairman Joel Hildebrand in Berkeley inviting me to join the faculty of the Department of Chemistry. The Salary would be 2,000.00 per annum. That was nearly 167 dollars a month It was a stellar opportunity... Linus Pauling and Wendell Latimer,... 

Traditionally, solubility parameters are given in (cal/cm ) = Hild(ebrands), in honor of the founder of the regular solution theory, Joel Hildebrand. Now, they are more commonly listed in (MPa) (= 1 (J/cm ) ). The solubility parameters were originally defined in conjunction with the regular solution theory, as discussed in Section 16.3.3.1. 

The heat of mixing term can be obtained from various theories. One valid possibility for nonpolar systems is the regular solution theory, introduced by Joel Hildebrand, which employs the concept of the solubility parameter. For a binary solvent(l)-polymer(2) system, the heat of mixing is given according to the regular solution theory ... 

FIGURE 328. Joel H. Hildebrand (1881-1983) became a faculty member under Gilbert N- Lewis at the University of California, Berkeley in 1913. In his influential Prin" ciples of Chemistry, first published in 1918, Hildebrand was the first to use the 1916 Lewis structures in a textbook (figures from Lewis 1923 book are shown here). Hildebrand s seventh and final edition was published in 1964, and his last chemistry paper was published during the year of his hundredth birthday. 

Joel H. Hildebrand and Robert L. Scott, The Solubility of Nonelectrolytes, 3rd Ed., Reinhold Publishing Corp., New York, 1950, p. 252. 

Hildebrand pointed out that the order of solubility of a given solute in a series of solvents is determined by the internal pressures of the solvents. Later, Scatchard introduced the concept of cohesive energy density into Hildebrand s theories. The solubility parameter is a numerical value that indicates the relative solvency behavior of a specific solvent. It is derived from the cohesive energy density of the solvent, which in turn is derived from the heat of vaporization. In 1936 Joel, H. Hildebrand proposed the square root of the cohesive energy density as a numerical value indicating the solvency behavior of a specific solvent ... 

The shades of time have been drawn, and one has very little chance of first-hand accounts of this important era in the development of electrochemistry. The authors were fortunate in this respect to have a letter from Professor Joel Hildebrand 22), who worked in Nernst s lab in 1907. Professor Hildebrand said that he could recall nothing of this controversy regarding the choice of the hydrogen electrode as the null point of the electromotive series. Thus the matter appears to have been settled by 1907, and research had gone on to other things. 

Letter from Joel H. Hildebrand to C. E. Moore, dated Dec. 12, 1981. 

Franz Frederick Exner developed a rotating anode expressly for industrial analytical practice that greatly reduced the time needed for analysis. The next year, Smith and another doctoral student, Joel Henry Hildebrand, created a double-cup mercury cathode by explicitly borrowing the basic operating principle of Dow Chemical Company s Castner-Kellner electrolytic cell. These inventions illustrate the interrelationship between industrial and academic science in the early twentieth century that produced a flow of ideas and methods in both directions. 

Three years later Joel Henry Hildebrand (1881-1983), one of Smith s doctoral students, developed an improved configuration for the mercury cathode during the course of his dissertation research. Hildebrand s thesis attempted the simultaneous electrolytic determination of both components of various electrolytes, especially sodium chloride. He pointed out that little work had been done previously on the electrolysis of salts or anions. Smith s preliminary study in 1903 of simultaneous... 

Joel H. Hildebrand and Robert L. Scott, The Solubility of Nonelectrolytes, 3rd edition. 

Lt. Col. Joel H. Hildebrand, "The Organization and Work of Hanlon Field, Industrial and Engineering Chemistry, 11 (1919), 291-92. 

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