1. Single Bond Rule:
If all the oxygens bonded to the nonmetal are single
covalent bonds, then the charage on the -ate
polyatomic ion is exactly the same as the charge
on the -ide central atom's ionic charge.
2. Double Bond Rule:
A double bond reduces the need for two electrons,
therefore increasing the charge from 3- to 1- or 4- to 2-
in the polyatomic ion (or adds +2 to the theorical charge)
3. Hydrogen Rule:
Hydrogens plug electron holes on the oxygen,
therefore decreasing the need for one electron
(or adds +1 to the charge of the polyatomic ion)
4. Transitional Metal Rule:
All transitional metal -ate polyatomic ions are 2-
(Per means more, but more charge-not more oxygen
add +1 to the formula in Permanaganate)