Formulas for Ionic Compounds with Polyatomic Ions http://www.BCLearningNetwork.com. 0:06this video will show you how to write 0:08chemical formulas for ionic compounds 0:10that contain polyatomic ions a 0:14polyatomic ion is a9 that contains more 0:16than one atom it can also be thought of 0:19as a group of atoms which acts as a 0:21single unit and has its own unique 0:23charge an example of a polyatomic ion is 0:27the nitrate ion which has the formula 0:29and all three and has an overall charge 0:32of negative 1 0:33here’s a simple drawing of a nitrate ion 0:36it maintains the structure when it forms 0:39compounds the bonds between a no Adams 0:42do not break so it remains as a no 0:45three- and IM table provided in science 0:4810 gives the names formulas and charges 0:51of many common polyatomic ions the only 0:55positive polyatomic ion this table is 0:58the ammonium ion on the very left at the 1:00top 1:01the rest are negative ions or anions and 1:04they are in alphabetical order