Honors chem test 3 Top numbers are charges that can be changed bottom numbers must stay same Ionic: A metal and Non metal formule Acid: Any formule that starts with H covalent: Two none metals combine polyatomic:All in its own script Note: Usually In () and has two or more capital leters next to it Ionic formule making rule: Step 1: Start with a metal "Ca2" Step 2: Place a non metal "Ca2N3" Step 3: Switch the numbers "Ca3N2" If their equal take out insted of swap