Gibbs potential

Table 48. Changes in Gibbs potential (AG) for some interactions in molten systems (after Amosov [295, 296]).

Gibbs potential changes, 136 Interaction temperature with carbonates, 27,35 Island-type structure, 60-81... 

The Kh values derived from kinetic data are close to those obtained by IR and NMR spectroscopies. An empirical formula for the evaluation of the hydrogen bond enthalpy and Gibbs potential was derived [47] ... 

The enthalpy is useful in considering isentropic and isobaric processes, but often it becomes necessary to rather deal with isothermal and isobaric processes. In such case one needs a thermodynamic function of T and P alone, defining the Gibbs potential G = U(T, P, Nj) as the Legendre transform of U that replaces entropy by temperature and volume by pressure. This transform is equivalent to a partial Legendre transform of the enthalpy,... 

Figure 9 Minima in the Gibbs potential in the vicinity of a co-existence curve curve and the critical point for a phase transition in a one-component system.

What is in a name Gibbs free energy, Free enthalpy, Gibbs energy, Gibbs potential... 

The Values of Gibbs Potential (—AG(298 K)) (kj mol-1) for Hydrogen Bonding ArOH Calculated by Equation (15.9), for Increments see Handbook [4]... 

The formula for the adiabatic Gibbs potential (Equation 6.51) is exact within the framework of the mean held description. As with the adiabatic Helmholtz potential, we examine it numerically following the Carlson theory of elliptic integrals [15-21], In order to make clear comparisons between the two types of free energy, the width D of the container is set to be 200 nm throughout (except for Figure 6.21). 

Gibbs potential, the units of which are related to the electrical potential by Nernst s equation ... 

The evolution of thermodynamically nonequilibrium systems (including the systems with complex stepwise chemical transformations, among them catalytic and biological reactions) occurs with respective changes in thermo dynamic parameters of the whole system or of its parts. Hence, nonequilib rium states are inherent in the nonequilibrium systems (both open and closed), while the relevant parameters and features of those states can be functions of time and/or space. For example, when a system is temperature and pressure isotropic, the Gibbs potential, G, of the entire system may be a function of not only temperature (T) and pressure (p) but also of time (t) ... 

Universal quantities T and p related to the whole system are not always appropriate for description of a nonequilibrium system due to its probable spatial inhomogeneity. In general, the nonequilibrium system needs to be characterized using local extensive parameters—for example, the Gibbs potential g(T(r, t), p(r, t)) per unit mass of the system matter. In this case. 

Chemical ij transformations of thermahzed components in the reaction groups are described also in terms of a change in the current values of the Gibbs potentials, A Gy, or the value of current affinity, A y, of the respec tive transformations. These parameters relate unambiguously (by defini tion) to one another as ... 

Here Po, is the current chemical potential of thermalized entity A, and G is the Gibbs potential of the entire system under consideration. 

The parenthesized equation matches the definition of the Gibbs potential, G, of the system ... 

Equation (1.17) is valid for the case of an open system, too—that is, when its Gibbs potential can be additionally varied throughout the flow or during the inflow of matter. Therefore, the rate of entropy production due to irreversible internal processes is... 

In other words, as expected, at a spontaneous evolution of the system at fixed p and T, its Gibbs potential decreases, dG < 0. Thus, the rate of entropy pro duction and energy dissipation in an open system at constant temperature and pressure is proportional to the rate of decreasing its Gibbs potential due to occurrence of irreversible spontaneous processes inside the system. 

Indeed, in a partial by equilibrium (in respect to T and p) system, the irreversibility and, as a result, a decrease in its Gibbs potential (dG < 0) and an increase in the entropy owing to internal processes (djS > 0) may be caused by either spontaneous phase or chemical transformations. 

The internal irreversible processes in this machine are accompanied by the entropy rise. The value of this rise is determined by variations in the total Gibbs potential of the system components and the components from the environment ... 

After one turn of the cycle in time x, the system is returned to its initial state. Hence, the changes in the thermodynamic Gibbs potential of the system wiU be zero in time x AG = 0, while AG < 0 due to the con sumption of alimentary substrates from the surrounding medium. The average rate of energy dissipation in the metabolic cycle is... 

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