A nonmetal is found by subtracting the group number from 8. Groups 4A and 0 do not usually form ions. Many of the transition metals have more than one charge. Some transition elements only have one charge so their names do not have the roman numeral. The charge on an ion is also called its oxidation number.
Some compounds have common names that are still used worldwide.
1. compounds composed of only 2 elements 2. 5.11 Ternary compounds contain atoms of 3 different elements. They usually contain a polyatomic ion. Watch for the ate and ite endings for the anions. When naming ternary compounds, watch for polyatomic ions.