Thermodynamic data, sources

Armstrong, G. T. Goldberg, R. N. "An Annotated Bibliography of Compiled Thermodynamic Data Sources for Biochemical and Aqueous Systems (1930-1975)" Nat. 

R. N. Goldberg, Compiled thermodynamic data sources for aqueous and biochemical systems An annotated bibliography (1930 1983), National Bureau of Standards Special Publication 685, Government Printing Office, Washington, DC, 1984. 

The LCM is a semi-theoretical model with a minimum number of adjustable parameters and is based on the Non-Random Two Liquid (NRTL) model for nonelectrolytes (20). The LCM does not have the inherent drawbacks of virial-expansion type equations as the modified Pitzer, and it proved to be more accurate than the Bromley method. Some advantages of the LCM are that the binary parameters are well defined, have weak temperature dependence, and can be regressed from various thermodynamic data sources. Additionally, the LCM does not require ion-pair equilibria to correct for activity coefficient prediction at higher ionic strengths. Thus, the LCM avoids defining, and ultimately solving, ion-pair activity coefficients and equilibrium expressions necessary in the Davies technique. Overall, the LCM appears to be the most suitable activity coefficient technique for aqueous solutions used in FGD hence, a data base and methods to use the LCM were developed. 

In addition to discussion of thermodynamic properties of organic substances and their measurement, this chapter (178 pp.) gives tables of entropy of fusion, and vapor pressures and a table of thermodynamic data sources for about 800 organic compounds (798 references). 

Compiled Thermodynamic Data Sources for Aqueous and Biochemical Systems An Annotated Bibliography (1930-1983)... 

This chapter provides a summary of the three laws of thermodynamics and the important defined functions and relations for applying these laws to materials systems. It is assumed that the reader has completed an introductory course on thermodynamics. The purpose of this chapter is to bring the reader back up to speed . An extensive reference list of thermodynamic data sources is also provided. 

The basic thermodynamic data for the design of such reactions can be used to assess the dissociation energies for various degrees of dissociation, and to calculate, approximately, tire relevant equilibrium constants. One important source of dissociation is by heating molecules to elevated temperamres. The data below show the general trend in the thermal dissociation energies of a number of important gaseous molecules. 

Extensive tabulations of standard enthalpies of formation and related thermodynamic data can be found in the literature.5 Table 9.1 summarizes selected values from these sources. 

The changes in free energy of formation of Reaction (1) are shown in Fig. 2.1 as a function of temperature. " The values of AG were calculated using Eq. (1) above for each temperature. The Gibbs free-energy values of the reactants and products were obtained from the JANAF Tables.1 Other sources of thermodynamic data are listed inRef 6. These sources are generally accurate and satisfactory forthe thermodynamic calculations of most CVD reactions they are often revised and expanded. 

Many sources of thermodynamic data are now availableinclud-ing the following ... 

The Internet has become the best source for thermodynamic data. Run a search on something like chemical thermodynamic data on any serious search engine, and you will hnd multiple sources, most of which allow free downloads. The data in the standard handbooks, e.g. Perry s Handbook (see Suggestions for Further Reading section of Chapter 5), are still correct but rather capricious in scope and likely to be expressed in archaic units like those sprinkled here and there in this book. 

Some points should be noted from this example. Firstly, ideal gas behavior has been assumed. This is an approximation, but it is reasonable for the low pressure assumed in the calculation. Later the calculation will be repeated at higher pressure when the ideal gas approximation will be poor. Also, it should be clear that the calculation is very sensitive to the thermodynamic data. Errors in the thermodynamic data can lead to a significantly different result. Thermodynamic data, even from reputable sources, should be used with caution. 

Lide, D. R., Ed. (2003). CRC Handbook of Chemistry and Physics, 84th ed. CRC Press, Boca Raton, FL. Structural and thermodynamic data are included for an enormous number of inorganic molecules in this massive data source. 

In most circumstances, it can be assumed that the gas-solid reaction proceeds more rapidly than the gaseous transport, and therefore that local equilibrium exists between the solid and gaseous components at the source and sink. This implies that the extent and direction of the transport reaction at each end of the temperature gradient may be assessed solely from thermodynamic data, and that the rate of transport across the interface between the gas and the solid phases, at both reactant and product sites, is not rate-determining. Transport of the gaseous species between the source of atoms and the sink where deposition takes place is the rate-determining process. 

The thermodynamic data for K+ complexes of dibenzo-18-crown-6 [11] in aprotic solution show that AAG + AGU (K+) changes with solvent (Table 16). Although the data have been collected from several sources, they would seem to indicate that the cation is more exposed to interactions with the solvent in crown-ether complexes than in cryptates. Hence, the term... 

The choice of a given database as source of auxiliary values may not be straightforward, even for a thermochemist. Consistency is a very important criterion, but factors such as the publication year, the assignment of an uncertainty to each value, and even the scientific reputation of the authors or the origin of the database matter. For instance, it would not be sensible to use the old NBS Circular 500 [22] when the NBS Tables of Chemical Thermodynamic Properties [17], published in 1982, is available. If we need a value for the standard enthalpy of formation of an organic compound, such as ethanol, we will probably prefer Pedley s Thermodynamic Data and Structures of Organic Compounds [15], published in 1994, which reports the error bars. Finally, if we are looking for the standard enthalpy of formation of any particular substance, we should first check whether it is included in CODATA Key Values for Thermodynamics [16] or in the very recent Active Thermochemical Tables [23,24],... 

Reversible cell potentials have been the source of much thermodynamic data on aqueous electrolytes. In recent years, this technique has been extended to nonaqueous solutions and to molten salt systems. Its use for aqueous solutions, relative to other techniques, has decreased. Various ion specific electrodes have been developed in recent years. These are used primarily in analytical chemistry and have not produced much thermodynamic data. 

Sources of thermodynamic data which the authors have found to be valuable in hydrometallurgical applications have been assembled in Table II. 

Burcat [ Thermochemical Data for Combustion Calculations, in Combustion Chemistry. (W. C. Gardiner, Jr., ed.), Chapter 8. John Wiley Sons, New York, 1984] discusses in detail the various sources of thermochemical data and their adaptation for computer usage. Examples of thermochemical data tit to polynomials for use in computer calculations are reported by McBride, B. J Gordon, S., and Reno, M. A., Coefficients for Calculating Thermodynamic and Transport Properties of Individual Species, NASA, NASA Langley, VA, NASA Technical Memorandum 4513, 1993, and by Kee, R. J., Rupley, F. M and Miller, J. A., The Chemkin Thermodynamic Data Base, Sandia National Laboratories, Livermore, CA, Sandia Technical Report SAND87-8215B, 1987. 

Data for other substances can be obtained from the following critical compilations and online in the NIST Chemistry WebBook at http //www.webbook.nist.gov/ chemistry/ or from the NIST-TRC Databases available on disk. (Information can be found at http //www.nist.gov/srd/thermo.htm, or at http //srdata.nist.gov/ gateway/gateway keyword = thermodynamics.) An exhaustive list of earlier sources of tabulated thermochemical data can be found in Volume 1 of Chemical Thermodynamics, A Specialist Periodical Report [2]. A useful list of websites containing thermodynamic data is available at http //tigger.uic.edu/ mansoori/ Thermodynamic.Data. and.Property.html. 

Table 5.69 lists thermal expansion and compressibility factors for some Si02 polymorphs, according to the databases of Saxena et al. (1993) and Holland and Powell (1990). Table 5.70 lists thermodynamic data for the various Si02 polymorphs according to various sources. 

There are a number of other data bases of valuable numeric information which are being built and obtained or expanded from existing sources. These Include IR, aquatic toxicity, partition coefficients and thermodynamic data. Anyone interested in the status of these and other such CIS projects is welcomed to write to either of the authors for a copy of the CIS status reports, an informal progress report issued every six months jointly by EPA and NIH. 

Relevant data extracted from activity measurements in the Fe-C phase were later included in the assessment by Zener (1946) and Darken and Smith (1951). All this work followed a traditional approach solely based on thermodynamic data derived under equilibrium conditions. By contrast, Kaufman and Cohen (1958) showed that the data of Johannson (1937) were more consistent with information derived from Fe-based martensite transformations than the interpretation used by Darken and Smith (1951). Together with the work of Svechnikov and Lesnik (1956) this was a notable attempt to combine thermodynamic information derived from low-temperature metastable transformations with those from more traditional sources. 

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