Final answer:
The correct name for CoCO₃ is cobalt (II) carbonate, specifying the +2 charge of the cobalt ions in the compound.
Step-by-step explanation:
The correct name for the compound CoCO₃ is cobalt (II) carbonate. This compound is made up of cobalt ions and carbonate ions. The cobalt ion in this compound has a 2+ charge. Cobalt can have more than one possible charge, but since carbonate (CO₃⁻) has a 2⁻ charge, and there is only one cobalt ion for each carbonate ion, the cobalt must be in the +2 oxidation state. Therefore, the Roman numeral (II) is used in the name to indicate the charge of the cobalt ions.