Kistiakowsky

Remarkably accurate experimental results have been obtained, also by Kistia-kowsky (Conant and Kistiakowsky, 1937), which permit indirect calculation of the enthalpy change of this isomerization AThe enthalpy diagram for isomcn/atioii of 2-butciic is given in Fig. 5-.5. We shall use TINKER and PCMODEL U) (ind the length of each arrow in Fig. 5-5. We shall also use the PCMODEL GUI. a powerful tool for tile construetion. 

Take the Final Function Value of TINKER as the steric energy for this calculation. Compare the results with each other and with a standard value from a good elementar-y organic chemistry text (e.g., Ege, 1994). Calculate for the reaction cis trans and compare it with a standard text and with Kistiakowsky s original value. Kistiakowsky s original work was carried out at 355 K, but the temperature difference between 298 K and 355 K cancels for this isomerization. 

If has long been known that the enthalpy of hydrogenalion of benzene (49.8 kcal moU Conant and Kistiakowsky, 1937) is not the same as three times the enthalpy of hydrogenation of cyclohexene (3 x 28.6 kcal moU ). Evidently, the double bonds that w e write in the Kekule structure of benzene... 

Draw an enthalpy level diagram showing how Kistiakowsky was able to... 

Professor s. w. benson Professor sir Frederick dainton Professor G. gee the late Professor p. goldfinger Professor g. s. hammond Professor w. jost Professor g. b. kistiakowsky Professor v. N. kondratiev Professor k. j. laidler Professor m. magat Professor sir harry melville Professor G. natta Professor r. g. w. norrish Professor s. okamura Professor sir eric rideal Professor n. n. semenov Professor z. g. szab6 Professor o. wichterle... 

The heats of hydrogenation for a number of unsaturated compounds are available from the work of Kistiakowsky and collaborators, and in a few cases from accurate heats of formation of the monomer and the reference compound can be estimated... 

The heats of hydrogenation of the olefins are derived from measured heats of hydrogenation by Kistiakowsky and co-workers (see also Ref. 43). Those of the dienes have been obtained from heats of formation of butadiene and of isoprene and the heats of formation of the corresponding mono-olefins Heats of hydrogenation of the last four monomers listed in the table are from direct measurements by Kistiakowsky and co-workers. ... 

A semi-empirical equation was introduced by Kistiakowsky and Wilson and took the following form ... 

Kistiakowsky and Smith [J. Am. Chem. Soc., 56 (638), 1934] have studied the kinetics of the cis-trans isomerization of isostilbene. The reaction is believed to be pseudo first-order in both the forward and reverse directions under the experimental conditions used by these investigators. 

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