Final answer:
Nickel(II) carbonate is the correct IUPAC name for the compound Ni₂CO₃, as it is composed of Ni2+ ions and carbonate ions.
Thus, none of the provided options (a) Nickel(II) oxide, (b) Dinickel trioxide, (c) Nickel trioxide, (d) Nickel (III) oxide are correct.
Step-by-step explanation:
The correct name for the compound Ni₂CO₃ is nickel(II) carbonate. This is an ionic compound composed of Ni2+ ions and the carbonate ion (CO₃2-). Nickel can exhibit multiple oxidation states, but in this compound, each nickel ion has an oxidation state of +2. The II in nickel(II) reflects that oxidation state, and the carbonate is the polyatomic ion.