Hi guys. I'm was doing redox reactions and got confused between a polyatomic ion and a regular chemical compound. I was dealing with a SO2 on the products side. I thought it was hyposulphite and would following the charge of 2-. My teacher told me that this was sulphur dioxide instead. How can I distinguish between them? From what she told me, if I see what looks to be a polyatomic ion standing alone, is it just a regular compound?
ex: KPO4 is Potassium phosphate.
If I get PO4 + ? + ?----> ?
Would this PO4 that is standing alone be considered Phosphorus Tetroxide?