Bases, definition

For the sake of completeness, it is worthwhile to briefly discuss role of acid-base interactions in adhesion. In this context, the term acid refers to a Lewis acid (an electron acceptor) and a Lewis base (electron donor), rather than the more conventional acid and base definitions. The role of acid-base interactions in adhesion is discussed in detail by Lee [105]. 

When developed, this theory proved to be more general than the theory of Lewis, for it includes all the above acid-base definitions and also includes oxidation-reduction reactions. 

The various acid-base definitions are summarized in the Venn diagram (Fig. 2.1). From this it can be seen that the Usanovich definition subsumes the Lewis definition, which in turn subsumes all other definitions (i.e. Arrhenius, Bronsted-Lowry, Germann-Cady-Elsey, Lux-Flood). 

Jensen, W. B. (1978). The Lewis acid-base definitions a status report. Chemical Reviews, 78, 1-22. 

TABLE 67-3. Pathogen-Based Definitive Treatment for Central Nervous System Infections... 

See Table 67-1 for empirical treatment recommendations. cSee text for specific recommendations for use of adjunctive dexamethasone in adults with bacterial meningitis. dSee Table 67-3 for pathogen-based definitive treatment recommendations. (Adapted, with permission, ref. 14.)... 

In silicate melts and other nonprotonated solvents, the Bronsted-Lowry equation is not applicable and is conveniently replaced by the Lux-Flood acid-base definition (Lux, 1939 Flood and Forland, 1947), according to which free oxygen 0 replaces A basic oxide is one capable of furnishing oxygen ions, and an acidic oxide is one that associates oxygen ions ... 

Although many other acid-base definitions have been proposed and have been useful in particular types of reactions, only a few have been widely adopted for general use. Among them are those attributed to Arrhenius (based on hydrogen and hydroxide ion formation), Br0nsted-Lowry (hydrogen ion donors and acceptors), and Lewis (electron pair donors and acceptors) [6,67-70]. 

Likewise any reactivity-based definition would require some arbitrary choice of reaction rate. Which reaction would be used What minimal rate would be required What conditions of temperature, solvent, or acidity would be chosen for the definition As a practical matter, such a dehnition could not be applied to any unknown species for the simple reason that reaction rates are, at this point in time, notoriously difficult to predict from first principles. 

Experimental work providing information on reaction kinetics— the time dependence of reactants and products under defined conditions—served indispensably to correlate structure-reactivity data and to provide estimates of transition state energies. Theory-based definitions of transition structures gave some clues as to how reactions might actually take place. But the dynamic aspects of chemical reactions remained inaccessible, or only poorly accessible. 

The attentive student may be concerned that the concept of ideal solution as introduced in Chapter 6 is possibly inconsistent with the usage of that term as defined in (7.45a-c). However, Sidebar 7.8 demonstrates that these definitions of solution ideality are in fact consistent. We may therefore regard chemical potential-based definitions of binary solution ideality [cf. (6.57)],... 

An example of the different points of view and different tastes in the matter of acid-base definitions was provided to one of the authors in graduate school while attending lectures on acid-base chemistry from two professors. One Felt that the solvent system was very useful, but that the Lewis concept went too far because it included coordination chemistry. The second used Lewis concepts in all of his work, but felt uncomfortable with the Usanovich definition because it included redox chemistry To the latter s credit, however, he realized that the separation was an artificial one, and he suggested the pyridine oxide example given above. 

Antiferromagnetism, 467-468 Aprotic solvents, 369-373 Aqueous solvents, and non-aqueous solvents. 359-386 Arachno structures, 798-800, 807 Aragonite, 98, 953 Arene complexes, 681-683 Arrhenius acid-base definition, 319... 

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