Calculation of equilibrium compositions

The standard Gibbs energy change of reaction, is used ia the calculation of equilibrium compositions the standard heat of reaction, is used iu... 

The standard Gibbs-energy change of reaction AG° is used in the calculation of equilibrium compositions. The standard heat of reaclion AH° is used in the calculation of the heat effects of chemical reaction, and the standard heat-capacity change of reaction is used for extrapolating AH° and AG° with T. Numerical values for AH° and AG° are computed from tabulated formation data, and AC° is determined from empirical expressions for the T dependence of the C° (see, e.g., Eq. [4-142]). 

As it was previously noted, Cp data are available only for C60H36 in the temperature range of 5-340 K. The heat capacity of other crystalline C60H2n have not been measured probably due to absence of the required amount of pure samples. However, thermodynamic properties of the hydrofullerenes can be calculated as accurately as it is required for calculation of equilibrium composition of their reactions. 

II 6.4 Calculations of Equilibrium Compositions for Systems of Biochemical Reactions... 

Systems of biochemical reactions like glycolysis, the citric acid cycle, and larger and smaller sequential and cyclic sets of enzyme-catalyzed reactions present challenges to make calculations and to obtain an overview. The calculations of equilibrium compositions for these systems of reactions are different from equilibrium calculations on chemical reactions because additional constraints, which arise from the enzyme mechanisms, must be taken into account. These additional constraints are taken into account when the stoichiometric number matrix is used in the equilibrium calculation via the program equcalcrx, but they must be explicitly written out when the conservation matrix is used with the program equcalcc. The stoichiometric number matrix for a system of reactions can also be used to calculate net reactions and pathways. 

CALCULATIONS OF EQUILIBRIUM COMPOSITIONS FOR SYSTEMS OF BIOCHEMICAL REACTIONS... 

Calculation of equilibrium compositions of a single biochemical reaction or a system of biochemical reactions at specified pH... 

R. A. Alberty, Calculation of equilibrium compositions of large systems of biochemical reactions, J. Phys. Chem. 104 B 4807-4814 (2000). 

In general, this approach may be used in the evaluation of those properties for which the ideal behavior of the system is physically defined, e.g. for Gibbs energy of mixing and the molar volume. The procedure can be demonstrated by means of the calculation of equilibrium composition based on the measurement of density in the system A-B in which the intermediate compound AB is formed. The compound AB undergoes at melting a partial thermal dissociation. 

Brinkley, S. R., Jr. (1947). Calculation of equilibrium composition of systems of many constituents. J. Chem. Phys. 15, 107-110. 

The above discussion considers only die calculation of equilibrium compositions xf and xf at a single temperature. The temperature dqiendence of xf and xf, as represented by a liquid-liquid solubility diagram, is also of interest. This temperature dependence enters the equilibrium formulation through the temperature dqiendence of the parameters in the assumed oqnession fiw thermodynamically, it is determined by the behavior of the molar excess enthalpy If a binary liquid system is described by the Porter equation,... 

Table 2. Iterative calculation of equilibrium composition of oxidation of propane with air...

From this point onward, the procedure is identical with the original one, as the calculation of equilibrium composition depends on the minimum of the function F n). This minimum can be found by solving a set of equations obtained when partial derivatives of the function F(n) with respect to the individual numbers of moles are made equal to zero. 

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