Thermochemistry foundations

Leicester, Henry M. (1951). Germain Henri Hess and the Foundation of Thermochemistry. Journal of Chemical Education 28 581-583. 

KnmJ and Watts ET (1991) In Third International Conference on Fundamentals of Adsorption (A B Metsmann and S E Scholl, eds), Engineering Foundation, New York, p 445 Kubaschewski O andHultgrenR (1962) In Experimental Thermochemistry, val II (HA Skinner, ed). Interscience Publishers, London, p 351 LangeKR (1963)/ ColloidSci 18,65... 

As described in the Introductory Chapter, attention was focused [1] prior to 1961 mainly on the morphology of the cool-flame and ignition regions, rates were followed by pressure change, and essentially chemical techniques were used for product analysis. The acceptance of free radicals, followed by the masterly and elegant Semenov theory [2], which established the principles of branched chain reactions, provided the foundation for modern interpretations of hydrocarbon oxidation. This chapter builds on these early ideas, and pioneering experiments such as those carried out by Knox and Wells [3] and Zeelenberg and Bickel [4], to provide a detailed account of the reactions, thermochemistry and detailed mechanisms involved in the gas-phase chemistry of hydrocarbon oxidation. 

Without continuous support from the National Science Foundation and the Department of Energy, much of what is reported here would not have been done. Without the flexibility to explore new directions and interconnections among low temperature geochemistry, high temperature mineral physics, and materials science, this work would have been intellectually poorer. I thank Bill Luth for pointing out to me, nearly 15 years ago, that the thermochemistry of low temperature materials is scientifically interesting, societally relevant, and fundable. I thank Mandar Ranade for providing data that will be part of his Ph D. dissertation. 

Using an ice calorimeter, he and Laplace in 1783 measured the specific heats and the heat evolved in comhustion and respiration, thus laying the foundations of thermochemistry, both on experimental and theoretical grounds, since the authors stated the principle that as much heat is required to decompose a compound as is liberated on its formation from the elements. ... 

In all, Lavoisier s contributions span the entire field of modem chemistry— from the concept of chemical elements to the law of indestmctibility of matter and conservation of mass in chemical transformations, from the theories of combustion to the foundation of thermochemistry, from chemical nomenclature to the mathematization and quantification of chemistry. Bertholet describes Lavoisier s influence on chemistry as La revolution chimique. It has been noted that a book on chemistry written before his time would not be intelligible to a student unacquainted with the history of chemistry, while Lavoisier s Trade elementaire de Chimie reads like a rather old edition of a modern textbook. 

Thermochemistry—The foundations of the branch of physical chemistry dealing with thermochemistry was laid by Lavoisier and Laplace, who through their collaborative efforts showed that the heat evolved in a reaction is equal to the heat absorbed in the reverse reaction. They investigated the specific and latent heats of a number of substances, as well as the amount of heat generated in combustion. It was Hess who in 1840 enunciated the law that now bears his name—Hess s law —that the evolution of heat in a reaction is the same whether the process is accomplished in one step or in a number of stages. As an illustration, the heat of formation of CO2 is the sum of the heat of the formation of CO and the heat of oxidation of CO to C02. ... 

Berthelot obtained ethyl peroxide from ether and ozone.He investigated photochemical reactions. His work on galvanic cells, partition coefficient, reaction velocity and equilibrium, and thermochemistry, is mentioned elsewhere. He analysed ancient metallic and other objects from Egypt and Mesopotamia, showing that the earliest so-called bronzes were pure copper, that an ancient Sumerian vase was of pure silver, and a box from Egypt was in part platinum-iridium. This work laid the foundations of chemical archaeology. His fundamental work on the history of chemistry is dealt with in Vol. I. One of his most important early researches, on glycerine, has been left over for consideration and will now be taken up. 

The study of affinity from another aspect was contained in the attempts to find a measure of the chemical forces by the amount of heat given out in a chemical reaction. The importance of thermal phenomena in chemical reactions was realised by Lavoisier and Laplace (1784), who laid the foundations of thermochemistry (see Vol. Ill, p. 426). They assumed that the amount of heat evolved in a chemical reaction is equal to that absorbed in the reverse reaction, and measured some specific heats and the amount of heat evolved in reactions, in combustion, and respiration. Persoz regarded both Lavoisier s caloric theory of combustion and Berzelius s electrochemical theory (see p. 169) as unsatisfactory, and concluded that there is no means of explaining the heat developed in chemical reactions . 

In the Traite Lavoisier described an ice calorimeter, which he had devised in conjunction with Pierre Simon de Laplace (1749-1827) to measure the amount of caloric evolved in chemical changes. These experiments laid the foundations of thermochemistry (Chapter 13). 

Black not only introduced the concept of latent heat, but also showed that a quantity of heat could be estimated by measuring the amount of ice it caused to melt. Lavoisier and Laplace employed this principle in their ice calorimeter (Figure 13.1). Between 1782 and 1784 Lavoisier and Laplace used this apparatus to measure the quantity of heat evolved in a number of chemical changes and thus laid the foundations of thermochemistry. 

Marchenko, G.N. and Tsvetkov, V.G., Solvation and thermoehemistiy of nonaqueous cellulose solutions. Thermochemistry of cellulose nitrate ethers formation. In Physical-Chemical Foundations and Hardware Implementation of the Teehnology of Pyroxylin Gimpowder Manufacturing. Cellulose Nitrates, Marchenko, G.N., Ed., Kazan FEN Publ., 2000, vol. 1, pp. 196-282 (in Russian). 

Laplace Pierre Simon (1749-1827) Fr. math., laid foundation of thermochemistry, theory of probability, made much use of potential partial differential equations since named after him, conducted experiments of specific heat and heat of combustion, developed ice calorimeter LaViolette Paul A. (1938 —) US. astrophys., developer of unusual subquantum kinetics and continuous creation model of the universe, and novel approach to microphysics that accounts for forces in a unified maimer Lavoisier Antoine Laurent (1743—1794) Fr. chem., discovered relation between combustion and oxygen, divided substances into elements and compounds, explained respiration, disproved phlogiston, introduced quantitative methods to chemistry... 

Memoir on Heat (with Laplace). This famous memoir, which laid the foundations of thermochemistry, describes what is called a machine , which was later named the ice calorimeter . Black said I am told it was contrived by Laplace. It consisted (Fig. 39) of an inner vessel bb containing crushed ice,... 

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