Gibbs energy of dissociation

Thus at x = j the Gibbs energy of formation of the solid compound must equal the right side of both Eq. (90) and Eq. (91). When AG°[AC(s)] is a large negative number and the solid compound is very stable, then z must be near unity and the Gibbs energy of dissociation of the ac species AG° must be approximately equal to — AG [AC(s)] if the interaction coefficients, and 0i4 + 4> are to remain relatively small. 

Gibbs energy of dissociation, table 293 pKa values of, table 293 strengths of 95-96 Acid -base catalysis 469,486 - 491 concerted 490 of mutarotation 487 Acid - base chemistry... 

With regard to the first dissociation step, the transfer Gibbs energy of dissociation, AG °(diss), pertains to the process... 

Make a list of the Gibbs energies of dissociation for all weak acids and convert them to pKs. ... 

The Gibbs energy of dissociation of a proton from any particnlar group can... 

Figure 7 Schematic representation of the range of application of various experimental methods to the investigation of the Gibbs energies of dissociation of metal oxides at 1273 K. (1) Direct dissociation (2) equilibria with CO + CO2 or Hg + HgO mixtures (3) e.m.f methods employing solid oxygen-ion electrolytes (4) equilibration method after Komarek and Kubaschewski...

In the case of hydrogen, for example, at a teiuperamre of 2500 K, the equilibrium constant for dissociation has the value, calculated from the tlrermo-dynamic relation between the Gibbs energy of formation and the equilibrium constant of 6.356 x 10 " and hence at a total pressure of 10 atmos, the degree of dissociation is 0.126 at 2500 K, which drops to 8.32 x 10 at 2000 K. 

The Gibbs energy of an electroneutral system is independent of the electrostatic potential. In fact, when substituting into Eq. (3.7) the electrochemical potentials of the ions contained in the system and allowing for the electroneutrality condition, we can readily see that the sum of aU terms jZjF f is zero. The same is true for any electroneutral subsystem consisting of the two sorts of ion and (particularly when these are produced by dissociation of a molecule of the original compound k into x+ cations and x anions), for which... 

Gibbs energy of electron transfer (AGe ) and the work terms for precursor formation (Wp) and successor dissociation (ws),... 

The solubility of an ionic solute, Sca, may be expressed in terms of its solubility product, The equilibrium between a pure solid salt, Cv+Av and its saturated solution in a solvent where it is completely dissociated to ions (generally having e > 40 see section 2.6) is governed by its standard molar Gibbs energy of dissolution... 

The development of a consistent theory for a dissociative electron transfer is a recent challenge in the field of theoretical electrocatalysis. Progress in this field of electrochemistry has involved the use of an harmonic Morse curves [25] instead of harmonic approximations. Applying the principles of the theory of the activated complex to adiabatic dissociative electron transfer reactions, the work of Saveant resulted in the following expressions [24] for the Gibbs energy of activation... 

The partial structure factors for binary (Bhatia and Thorton, 1970) and multicomponent (Bhatia and Ratti, 1977) liquids have been expressed in terms of fluctuation correlation factors, which at zero wave number are related to the thermodynamic properties. An associated solution model in the limits of nearly complete association or nearly complete dissociation has been used to illustrate the composition dependence of the composition-fluctuation factor at zero wave number, Scc(0). For a binary liquid this is inversely proportional to the second derivative of the Gibbs energy of mixing with respect to atom fraction. 

Equations (109) and (110) imply that Eq. (17) for the auxiliary condition on ASM is satisfied. The next independent constraint applied is then the requirement that the relative chemical potential of the species ac must equal the Gibbs energy of formation of AC(s) at the congruent melting point. This allows one to express the entropy of dissociation of ac as... 

Logarithms of formation constants, which are proportional to the Gibbs energies of association, are often tabulated. The logarithms of formation constants and pK t values of dissociation constants are identical (Eq. 6-72) and are a measure of the standard... 

While the examples chosen here concern only dissociation of protons, the Hammett equation has a much broader application. Equilibria for other types of reactions can be treated. Furthermore, since rates of reactions are related to Gibbs energies of activation, many rate constants can be correlated. For these purposes the Hammett equation can be written in the more general form in which k may be either an equilibrium constant or a rate constant.13 The subscript / denotes the reaction under consideration and i the substituent influencing the reaction. 

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