The carbonate ion CO3-2 has three possible resonance structures. These structures are formed by the delocalization of the electrons in the double bond between the carbon and one of the oxygen atoms, as well as the negative charges on the other two oxygen atoms. The three resonance structures are as follows:1. A double bond between the carbon atom and one of the oxygen atoms, with a single bond to the other two oxygen atoms. One of the singly bonded oxygen atoms has a negative charge, and the other has a negative charge as well.2. A double bond between the carbon atom and the second oxygen atom, with a single bond to the first and third oxygen atoms. The first oxygen atom has a negative charge, and the third oxygen atom has a negative charge as well.3. A double bond between the carbon atom and the third oxygen atom, with a single bond to the first and second oxygen atoms. The first oxygen atom has a negative charge, and the second oxygen atom has a negative charge as well.These resonance structures contribute to the stability of the carbonate ion by delocalizing the negative charge across the three oxygen atoms. The electrons are not localized to a specific oxygen atom but are rather shared among all three. This delocalization of electrons leads to a more stable structure, as it lowers the overall energy of the ion. The actual structure of the carbonate ion is a hybrid of these three resonance structures, with each oxygen atom having a partial double bond character and a partial negative charge.