Final answer:
The formulas for the given ionic compounds are NaCl, K2SO4, CaCO3, and NH4 NO3.
Step-by-step explanation:
a) Sodium chloride: The formula for sodium chloride is NaCl. Sodium has a 1+ charge and chlorine has a 1- charge, so they combine in a 1:1 ratio to form the compound.
b) Potassium sulfate: The formula for potassium sulfate is K2SO4. Potassium has a 1+ charge and sulfate has a 2- charge, so two potassium ions are needed to balance the charge of one sulfate ion.
c) Calcium carbonate: The formula for calcium carbonate is CaCO3. Calcium has a 2+ charge and carbonate has a 2- charge, so they combine in a 1:1 ratio to form the compound.
d) Ammonium nitrate: The formula for ammonium nitrate is NH4 NO3. Ammonium has a 1+ charge and nitrate has a 1- charge, so they combine in a 1:1 ratio to form the compound.