Question: what is the difference between a compound and a polyatomic ion?
Answer: What is the difference between a polyatomic ion and an ionic compound? The most basic difference is that a polyatomic ion is a cluster of atoms with a net charge. An ionic compound is electrically neutral (no net charge). ... E.g. Sulfate (SO4 ^2-) is a polyatomic ion, unlike barium sulfate (BaSO4) which is a compound.