Which ion is represented by the formula CO3(2-)?

The formula CO3(2-) corresponds to the carbonate ion. This ion is made up of one carbon atom and three oxygen atoms, and it carries a net charge of -2. The structure of the carbonate ion features a central carbon atom bonded to three oxygen atoms, with one of the oxygen atoms forming a double bond with the carbon. The other two oxygen atoms are each singly bonded to the carbon and carry a negative charge, contributing to the overall -2 charge of the ion.

The naming conventions for polyatomic ions help differentiate among ions with similar components. For example, other ions like oxide, nitrate, and sulfate have different structures and formulas. An oxide ion (O2-) contains only oxygen and carries a -2 charge, while the nitrate ion (NO3-) consists of one nitrogen and three oxygens, with a -1 charge. The sulfate ion (SO4(2-)) has a similar structure to carbonate but contains sulfur at its center instead of carbon.

Thus, a thorough understanding of the structure and composition of the carbonate ion confirms that CO3(2-) represents carbonate.