Nitrogen does not typically form ionic compounds. It usually forms covalent compounds with other nonmetals.
The formula for Zinc Sulfide is ZnS, where Zinc has a +2 charge and Sulfur has a -2 charge, therefore balancing out.
The formula for Sodium Carbonate is Na2CO3, as sodium has a +1 charge, carbonate has a -2 charge, and two sodium ions are needed to balance out the carbonate ion.
