Here's a breakdown:

* C represents a carbon atom.

* O represents an oxygen atom.

* 3 indicates that there are three oxygen atoms.

* ²⁻ represents the overall charge of the ion, which is -2.

Keep in mind that this is the formula for the carbonate ion. When carbonates form compounds, they combine with other elements or groups to balance the charge. For example:

* Calcium carbonate (CaCO₃)

* Sodium carbonate (Na₂CO₃)

* Potassium bicarbonate (KHCO₃)