Here's why and what the correct formula and name are:

* Nickel (Ni) has a +2 charge.

* Carbonate (CO3) has a -2 charge.

Since the charges are equal and opposite, the formula should be NiCO3.

The correct name is Nickel(II) Carbonate.

It's important to use the Roman numeral (II) to indicate the oxidation state of nickel because it can have multiple oxidation states.