Transformed thermodynamic properties table

Tables of Standard Transformed Thermodynamic Properties at 298.15 K for Biochemical Reactants at Specified pH and Ionic Strength... 

The relationships between the thermodynamic properties of chemical reactions and the transformed thermodynamic properties of biochemical reactions have been treated in several reviews (Alberty, 1993a, 1994c, 1997b, 2001 e). Recommendations for Nomenclature and Tables in Biochemical Thermodynamics from an IUPAC-IUBMB Committee were published in 1994 and republished in 1996. This report is available on the Web http llwww.chem.qmw.ac.uhlimbmbl thermodl. 

These tables apply to single sets of values of pH and ionic strength. A more general approach is to use the functions of ionic strength and pH for each reactant that give the values of standard transformed thermodynamic properties at 298.15 K. For reactants for which A,//0 is known for all species, functions of temperature, pH, and ionic strength can be used to calculate standard transformed thermodynamic properties at temperatures in the approximate range 273.15 to 313.15 K, as discussed in Section 4.9. 

Construction of Tables and Plots of Transformed Thermodynamic Properties of Inorganic Phosphate at 298.15 K... 

The functions derived in the preceding section can be added and subtracted to obtain standard transformed thermodynamic properties for enzyme-catalyzed reactions. The program deriveftiGHSNHrx is used to produce a list of functions for the reaction properties A, G A, H A, S °, and Nh for a typed-in reaction that can be used to calculate tables or make... 

Since the transformed thermodynamic properties of inorganic phosphate are each functions of four variables and we want to see how five transformed properties are affected, it is difficult to describe these dependencies, but Mathematica provides two ways. The first is to make a table, and the second is to make three-dimensional plots at a specified ionic strength. 

Table 5.1 Transformed thermodynamic properties of inorganic phosphate at temperatures 298.15 K, 313.15 K, pHs 5, 7, and 9, pMgs at 2, 4, and 6, and ionic strengths of zero and 0.25 M. Deeply nested lists like this are by default printed with successive dimensions alternating between rows and columns.

Chapters 3-5 have described the calculation of various transformed thermodynamic properties of biochemical reactants and reactions from standard thermodynamic properties of species, but they have not discussed how these species properties were determined. Of course, some species properties came directly out of the National Bureau of Standard Tables (1) and CODATA Tables (2). One way to calculate standard thermodynamic properties of species not in the tables of chemical thermodynamic properties is to express the apparent equilibrium constant K in terms of the equilibrium constant K of a reference chemical reaction, that is a reference reaction written in terms of species, and binding polynomials of reactants, as described in Chapter 2. In order to do this the piiTs of the reactants in the pH range of interest must be known, and if metal ions are bound, the dissociation constants of the metal ion complexes must also be known. For the hydrolysis of adenosine triphosphate to adenosine diphosphate, the apparent equilibrium constant is given by... 

The functions of pH and ionic strength and functions of temperature, pH, and ionic strength that yield standard transformed thermodynamic properties are produced in the package BasicBiochemDataS. These functions are used here to make the following four tables ... 

The Appendix contains a copy of the Mathematica notebook BasicBiochemDataS.nb, Tables of Transformed Thermodynamic Properties, the Glossary of Names of Reactants, the Glossary of Symbols for Thermodynamic Properties, a List of Mathematica programs, and Sources of Biochemical Thermodynamic Information on the Web. The Mathematica package BasicBiochemData3.m, which is also available at... 

In the sohd state, uranium metal exists in three aHotropic modifications. The transformation temperatures and the enthalpies of transformation are given in Table 5. The thermodynamic properties of uranium metal have been deterrnined with great accuracy and have been discussed (50). 

The thermodynamic changes for reversible, free, and intermediate expansions are compared in the first column of Table 5.1. This table emphasizes the difference between an exact differential and an inexact differential. Thus, U and H, which are state functions whose differentials are exact, undergo the same change in each of the three different paths used for the transformation. They are thermodynamic properties. However, the work and heat quantities depend on the particular path chosen, even though the initial and final values of the temperature, pressure, and volume, respectively, are the same in all these cases. Thus, heat and work are not thermodynamic properties rather, they are energies in transfer between system and surroundings. 

As the Gibbs function is a thermodynamic property, values of AG do not depend on the intermediate chemical reactions that have been used to transform a set of reactants, under specified conditions, to a series of products. Thus, one can add known values of a Gibbs function to obtain values for reactions for which direct data are not available. The most convenient values to use are the functions for the formation of a compound in its standard state from the elements in their standard states, as given in Tables 7.2... 

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