Next page Ionic bonds

You can use electronegativity differences to think of chemical bonds as having a percent ionic or a percent covalent character. The graph below plots percent ionic character versus AEN for a number of gaseous binary molecules. Use this graph to answer the questions on the next page. 

The forces of attraction between molecules are known as intermolecular forces. Intermolecular forces vary in strength but are generally weaker than bonds that join atoms in molecules, ions in ionic compounds, or metal atoms in solid metals. Compare the boiling points of the metals and ionic compounds in Figure 5.8 (on the next page) with those of the molecular substances listed. Note that the values for ionic compounds and metals are much higher than those for molecular substances. 

The bonding between atoms in compounds can be viewed as a range of electron sharing measured by electronegativity difference, AEN. This range contains three main classes of bonds—ionic, polar covalent, and covalent. Differences in electronegativity, AEN, are explained on the next two pages. 

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