Which of the following naming rules would apply to CaCO3?

metal cation + nonmetal anion (ide)

metal cation + (roman numeral valence) + nonmetal anion (ide)

polyatomic cation + nonmetal anion (ide)

metal + polyatomic anion

Metal (Ca) Polyatomic anion (CO3). You do not need to use the roman numeral because Ca is in group 1. The answer is metal + polyatomic or Calcium Carbonate

I believe the correct answer from the choices listed above is the first option. The naming rule that would apply to CaCO3 is should be metal cation + nonmetal anion (ide). The naming would be written as Calcium Carbonate. Hope this answers the question.