Models Lewis acid-base

The Lewis acid-base model is the most general of the three we have considered. 

Many years ago, geochemists recognized that whereas some metallic elements are found as sulfides in the Earth s crust, others are usually encountered as oxides, chlorides, or carbonates. Copper, lead, and mercury are most often found as sulfide ores Na and K are found as their chloride salts Mg and Ca exist as carbonates and Al, Ti, and Fe are all found as oxides. Today chemists understand the causes of this differentiation among metal compounds. The underlying principle is how tightly an atom binds its valence electrons. The strength with which an atom holds its valence electrons also determines the ability of that atom to act as a Lewis base, so we can use the Lewis acid-base model to describe many affinities that exist among elements. This notion not only explains the natural distribution of minerals, but also can be used to predict patterns of chemical reactivity. 

Note that the SO3 molecule, a Lewis acid, accepts an electron pair from the ion, a Lewis base. The Arrhenius, Bronsted-Lowry, and Lewis acid-base models are summarized in Table 18-2. 

All Bronsted-Lowry acids (proton donors) are also Lewis acids, and all Bronsted-Lowry bases (proton acceptors) are also Lewis bases. But the Lewis acid-base model is far more general in that it applies to reactions beyond just proton transfers. 

IBLG See questions from The Lewis Acid-Base Model ... 

Use the Lewis acid-base model to explain the following reaction. 

The Lewis acid-base model removes that restriction. A Lewis acid is a species that in an acid-base reaction, accepts an electron pair. In this reaction, a Lewis base donates the electron pair. 

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