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Free energy concentration and

The extent of these reactions will be determined by the reaction free energy and concentration for each of the impurities in the molten anode/electrolyte salt system. Americium can be used as an example of a very electropositive impurity ... [Pg.397]

To do so, let s derive an expression for the relation between cell potential and concentration based on the relation between free energy and concentration. Recall from Chapter 20 (Equation 20.13) that AG equals AG° (the free energy change when the system moves from standard-state concentrations to equilibrium) plus RT In Q (the free energy change when the system moves from nonstandard-state to standard-state concentrations) ... [Pg.703]

See also Free Energy and Useful Work, Free Energy and Concentration, Free Energy Change and the Equilibrium Constant... [Pg.957]

See also ATP as Free Energy Currency, Free Energy and Concentration (from Chapter 3), Important Points about AG (from chapter 3)... [Pg.965]

FIGURE 2.90 Relationship between changes in free energy and concentration of unfrozen water (a) and IPSD (bound cluster) size distributions (b) in frozen aqueous suspensions of silicalites calculated with the NMR cryoporometry (bound water) and MND (nitrogen) methods. [Pg.440]

The temperature dependences of concentrations of unfrozen water and benzene and the relationships between changes in the Gibbs free energy and concentrations of the unfrozen liquids (Figure 3.23) reveal that benzene can fill practically the total pore volume in contrast to water, which occupies only a portion of the pore volume (Figure 3.20a), since another portion of the pore volume is occupied by remained air bubbles in contact with hydrophobic basal planes of the adsorbent. Despite the total amount of unfrozen adsorbed water is 0.5 cmVg and a surface area in contact with unfrozen adsorbed water is 703 mVg that are smaller than the Vnano and 5nano values (Table 3.7), a portion of water remains out of pores since hydration is h=1.33 gig. Added chloroform displaces... [Pg.484]

A quantitative theory of rate processes has been developed on the assumption that the activated state has a characteristic enthalpy, entropy and free energy the concentration of activated molecules may thus be calculated using statistical mechanical methods. Whilst the theory gives a very plausible treatment of very many rate processes, it suffers from the difficulty of calculating the thermodynamic properties of the transition state. [Pg.402]

Spectator ion An ion that, although present, takes no part in a reaction, 279,82-83, 372-373,399 Spontaneity of reaction concentration and, 465-467,475-476q entropy and, 453-458 free energy and, 458-471 pressure effects, 465-467,475-476q process, 451-453 redox, 489-490... [Pg.697]

The conformation of macro- or polyions has been defined and discussed briefly in Section 4.1.1. The conformation of a polyion is determined by a balance between contractile forces, which depend on conformation free energy, and extension forces, which arise from electrical free energy. The extent of conformational change is determined by several factors. Changes are facilitated by the degree of flexibility of the polyion, and conformational change is greatest at low concentration of polyions. [Pg.79]

If k is expressed in liters per mole per second, the standard state for the free energy and entropy of activation is 1 mole/liter. If the units of k are cubic centimeters per molecule per second, the corresponding standard state concentration is 1 molecule/cm3. The magnitudes of AG and AS reflect changes in the standard state, so it is not useful to say that a particular reaction is characterized by specific numerical values of these parameters unless the standard states associated with them are clearly identified. These standard states are automatically determined by the units chosen to describe the reactant concentrations in the phenomenological rate expressions. [Pg.117]

There is a point at which these aggregates reach a critical size of minimum stability r and the free energy of formation AG is a maximum. Further addition of material to the critical nucleus decreases the free energy and produces a stable growing nucleus. The nucleation rate is the product of the concentration of critical nuclei N given by... [Pg.131]

Here scalar order parameter, has the interpretation of a normalized difference between the oil and water concentrations go is the strength of surfactant and /o is the parameter describing the stability of the microemulsion and is proportional to the chemical potential of the surfactant. The constant go is solely responsible for the creation of internal surfaces in the model. The microemulsion or the lamellar phase forms only when go is negative. The function/(<))) is the bulk free energy and describes the coexistence of the pure water phase (4> = —1), pure oil phase (4> = 1), and microemulsion (< ) = 0), provided that/o = 0 (in the mean-held approximation). One can easily calculate the correlation function (4>(r)(0)) — (4>(r) (4>(0)) in various bulk homogeneous phases. In the microemulsion this function oscillates, indicating local correlations between water-rich and oil-rich domains. In the pure water or oil phases it should decay monotonically to zero. This does occur, provided that g2 > 4 /TT/o — go- Because of the < ), —<(> (oil-water) symmetry of the model, the interface between the oil-rich and water-rich domains is given by... [Pg.161]

Here, it is fairly easy to push or to pull the weight in either direction. Some reactions however operate far from their true equilibrium position that is have a large /+, 103 or 1(G3). There is a large change of free energy and the reaction is said to be physiologically irreversible, that is under the conditions of temperature and concentration which prevail inside cells, the reaction is unidirectional (Figure 2.4). [Pg.38]

The integral is from V to V. With Equation 5.43 the disadvantage of the slowly converging Taylor series (Equation 5.40) is avoided and the contributions of internal modes properly evaluated. Also apparent differences between RPFR obtained via VPIE or LVFF can be successfully rationalized, and the excess free energies in concentrated solutions of isotopomers, one in the other, interpreted. Examples are given in Table 5.10. [Pg.171]

Rahaman and Hatton [152] developed a thermodynamic model for the prediction of the sizes of the protein filled and unfilled RMs as a function of system parameters such as ionic strength, protein charge, and size, Wq and protein concentration for both phase transfer and injection techniques. The important assumptions considered include (i) reverse micellar population is bidisperse, (ii) charge distribution is uniform, (iii) electrostatic interactions within a micelle and between a protein and micellar interface are represented by nonlinear Poisson-Boltzmann equation, (iv) the equilibrium micellar radii are assumed to be those that minimize the system free energy, and (v) water transferred between the two phases is too small to change chemical potential. [Pg.151]

The importance of interactions amongst point defects, at even fairly low defect concentrations, was recognized several years ago. Although one has to take into account the actual defect structure and modifications of short-range order to be able to describe the properties of solids fully, it has been found useful to represent all the processes involved in the intrinsic defect equilibria in a crystal (with a low concentration of defects), as well as its equilibrium with its external environment, by a set of coupled quasichemical reactions. These equilibrium reactions are then handled by the law of mass action. The free energy and equilibrium constants for each process can be obtained if we know the enthalpies and entropies of the reactions from theory or... [Pg.234]


See other pages where Free energy concentration and is mentioned: [Pg.1007]    [Pg.964]    [Pg.2334]    [Pg.689]    [Pg.689]    [Pg.1007]    [Pg.964]    [Pg.2334]    [Pg.689]    [Pg.689]    [Pg.538]    [Pg.255]    [Pg.159]    [Pg.36]    [Pg.697]    [Pg.381]    [Pg.131]    [Pg.180]    [Pg.239]    [Pg.79]    [Pg.49]    [Pg.166]    [Pg.77]    [Pg.12]    [Pg.17]    [Pg.37]    [Pg.659]    [Pg.30]    [Pg.179]    [Pg.146]    [Pg.156]    [Pg.179]    [Pg.538]    [Pg.88]   


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Energy concentration

Standard-state Free Energies, Equilibrium Constants, and Concentrations

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