## Chemistry: A Molecular Approach (3rd Edition)

To name binary molecular compounds, Greek prefixes are used to indicate how many of each element are in a compound. The more electronegative element is written last and its ending is changed to -ide. For example, $N_{2}O$ is dinitrogen monoxide. To name ionic compounds, the name of cation comes first followed by the anion's name. For monatomic atoms, the anion's name is changed to end in -ide. Nothing needs to be done for polyatomic ions. If the metal can form cations of different charges, the positive charge is given in parentheses in Roman numerals. For example copper (II) oxide (CuO).