Acids and Bases Revisited More Chemical Reactions

15 Acids and Bases Revisited More Chemical Reactions 

In Section 1.7 (p. 41), we introduced acids and bases. Now we know quite a bit more about structure and can return to the important subject of acids and bases in greater depth. In particular, we know about carbocations and carbanions, which play an important role in acid—base chemistry in organic chemistry The Lewis definition of acids and bases is far more inclusive than the Bronsted definition, which focuses solely on proton donation (Breasted acid) and acceptance (Breasted base). The archetypal Brensted acid-base reaction is the reaction between KOH and HCl to transfer a proton from HCl to HO. This reaction is a competition between the hydroxide and the chloride for a proton. In this case, the stronger base hydroxide wins easily (Rg. 2.57). 

In the Lewis description of acids and bases, any reaction between an empty orbital and a reactive pair of electrons in a filled orbital is an acid-base reaction. v nother way of putting this is to point out that the interaction between an empty orbital (Lewis acid) and a filled orbital (Lewis base) is stabilizing (Fig. 2.58). 

FIGURE 2.58 The interaction of a filled orbital (Lewis base) with an empty orbital (Lewis acid) is stabdizing. 

FIGURE 2.59 Three Lewis bases reacting with the methyl cation, a Lewis acid. 

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