The Ionic Bonding Model

The central idea of the ionic bonding model is the transfer of electrons from meted atoms to nonmetal atoms to form ions that come together in a solid ionic compound. For nearly every monatomic ion of a main-group element, the electron configuration has a filled outer level either two or eight electrons, the same number as in the nearest noble gas (octet rule). 

Problem Use partial orbital diagrams and Lewis symbols to depict the formation of Na and ions from the atoms, and determine the formula of the compound the ions form. Plan First we draw the orbital diagrams and Lewis symbols for the Na and O atoms. To attain filled outer levels, Na loses one electron and O gains two. Thus, to make the number of electrons lost equal the number gained, two Na atoms are needed for each O atom. 

FOLLOW-UP PROBLEM 9.1 Use condensed electron configurations and Lewis symbols to depict the formation of Mg mula of the ionic compound. 

You may be surprised to learn that the electron-transfer process by itself actually absorbs energy Consider just the electron-transfer process for the formation of lithium fluoride, which involves two steps—a gaseous Li atom loses an electron, and a gaseous F atom gains it  

Note that the two-step electron-transfer process by itself requires energy  

FOLLOW-UP PROBLEM 9.1 Use condensed electron configurations and Lewis 

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Oxidic surfaces in particular develop acid or basic properties which are important in catalysis. We will approach this subject first by taking as a starting point the ionic bond model [2]. The lattice is considered to consist of cations and anions held together by electrostatic interactions. Later we will discuss a more balanced theory that also accounts for covalent bonding aspects. 

For the heavier elements As, Sb, and Bi, further diversity in structure and stoichiometry is found. The ionic bond model becomes less useful as these species may be thought of as intermetallics, possessing metallic luster, and conduction or semiconduction properties. Typical examples include Na3Bi and NaBi, which becomes superconducting at low temperatures (<2.5 K). Further details will be found in the relevant article for each element, As, Sb, and Bi. Zintl anions of these elements are also known. ... 

Consideration of metal-nitrogen bond lengths in light of the ionic-bonding model advanced by Raymond (10) leaves little doubt that the bonding in the binary silylamide derivatives of the lanthanide elements is predominantly ionic (11). Indeed, all of the tris-silylamide derivatives of the p-, d-, and f-block elements can be viewed as being mainly ionic. 

Most ionic compounds do not conduct electricity in the solid state but do conduct it when melted or when dissolved in water. According to the ionic bonding model, the solid consists of immobilized ions. When it melts or dissolves, however, the ions are free to move and carry an electric current, as shown in Figure 9.9. 

An advantage of the ionic bonding model is that these energies can be calculated. This, in turn, allows one to estimate other properties of ionic solids, including mechanical properties. 

The Ionic Bonding Model Importance of Lattice Energy How the Model Explains the Properties Polar Covalent Bonds and Bond Polarity... 

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