Final answer:
The carbonate ion (CO3^2-) has three possible resonance structures, which are different ways to represent the electron distribution in the molecule. These forms illustrate that the actual structure of the ion is a hybrid with three bonds of equal length, characterized by a bond order of 1.33.
Step-by-step explanation:
The carbonate ion (CO32-) has three possible resonance structures. In resonance forms, the placement of electrons and bonds may differ, but the overall geometry remains constant. It's crucial to understand that these forms are simply different ways to depict the same molecule, with electrons being delocalized over the structure. For the carbonate ion, each resonance structure shows the carbon atom double-bonded to one oxygen atom and single-bonded to the other two oxygen atoms. However, experimental evidence shows that all three carbon-oxygen bonds are equally long, indicating that the actual structure is a resonance hybrid of the three forms, where each bond has a bond order of 1.33, meaning they are each part way between a single and a double bond. This resonance hybrid is more representative of the true electron distribution within the ion.