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How are binary ionic compounds named?

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Two diagrams show the three-dimensional structure of a methane molecule: panel A uses a ball-and-stick model with a central carbon atom connected to four hydrogen atoms in a tetrahedral arrangement, while panel B illustrates the bond angle of 109.5 degrees and bond length of 1.09 angstroms between carbon and hydrogen atoms. — chemical compound Methane, in which four hydrogen atoms are bound to a single carbon atom, is an example of a basic chemical compound. The structures of chemical compounds are influenced by complex factors, such as bond angles and bond length.

The nomenclature for binary ionic compounds—compounds consisting of two different elements—follows a standardized set of rules based on the names of the constituent ions.12

Naming Rules

Cation First: The positive ion (cation) is named first, followed by the negative ion (anion).12
Cation Name: A simple cation derived from a single atom retains the name of its parent element (e.g., $N a^{+}$ is sodium).12
Anion Name: A simple anion is named by taking the root of the parent element's name and adding the suffix -ide (e.g., $C l^{-}$ becomes chloride).12

Metals with Multiple Charges

When a metal can form more than one type of cation, the specific charge must be indicated using a Roman numeral in parentheses immediately following the metal's name. For example, $F e C l_{3}$ is named iron(III) chloride, while $F e C l_{2}$ is iron(II) chloride.12

Older nomenclature may use the suffixes -ic for the higher charge and -ous for the lower charge (e.g., ferric chloride and ferrous chloride, respectively).12