Naming Molecular Covalent Compounds and Writing Their Formulas

Naming Molecular (CoValent) Compounds and Writing Their Formulas 

Nonmetals tend to form covalent bonds with one another (see Chapter 5 for details). Compounds made up of nonmetals held together by one or more covalent bonds are called molecular (or covalent) compounds. 

Predicting how the atoms within molecules will bond with one another is a tricky endeavor because two nonmetals often can combine in multiple ratios. Carbon and oxygen, for example, can combine in a one-to-two ratio to form CO2 (carbon dioxide), a harmless gas you emit every time you exhale. Alternatively, the same two elements can combine in a one-to-one ratio to form CO (carbon monoxide), a poisonous gas. Clearly, having names that distinguish between these (and other) molecular compounds is useful. The punishment for sloppy naming can be death. Or at least embarrassment. 

Molecular compound names clearly specify how many of each type of atom participate in the compound. Table 6-2 lists the prefixes used to do so. 

Prefix Number of Atoms Prefix Number of Atoms 

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