Fiee energy defined

The numerical values of the terms a and p are defined by specifying the ionization of benzoic acids as the standard reaction to which the reaction constant p = 1 is assigned. The substituent constant, a, can then be determined for a series of substituent groups by measurement of the acid dissociation constant of the substituted benzoic acids. The a values so defined are used in the correlation of other reaction series, and the p values of the reactions are thus determined. The relationship between Eqs. (4.12) and (4.14) is evident when the Hammett equation is expressed in terms of fiee energy. For the standard reaction, o%K/Kq = ap. Thus,... 

In Eqn. 7-9 A and A are defined as the forward and the backward reaction affinities, respectively. A corresponds to the energy (fiee enthalpy) of the reactant particles and A corresponds to the energy (fioe enthalpy) of the product particles as shown in Eqn. 7-10 ... 

In these expressions Tq refers to the natural frequent as T (activated process) oiasT=Tg (fiee volume control). Above Tg the latter dependaice degenerates into Ardimiius form in terms of a scaled temperatureT" = T- Tg + C2, and even below Tg an effective temperature can be defined to ensure Ardienius form Thus for a e rdaxation the TSD peak can be fully analysed to provide an activation energy or shift temperature. 

Equations (4) and (5) exactly define the inside energy and the fiee enthalpy of the adsorbed layer, respectively. For definition of the thermodynamic equilibrium between the gas phase and the adsorbed layer, Eq. (4) should be differentiated ... 

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