Complex sentence: These can be simple ions such as the sodium (Na +) and chloride (Cl −) in sodium chloride, or complex polyatomic species such as the carbonate (CO 3 2 −) in calcium carbonate.
Split into simpler sentences: These can be simple ions as in the sodium (Na +) and chloride (Cl −) in sodium chloride. Many ionic compounds are composed of more complex polyatomic species such as the carbonate (CO 3 2 −) in calcium carbonate.