What does the subscript mean in the chemical formula CO2?

In the example of carbon dioxide, CO2, the subscript 2 following the oxygen symbol O says that there are two oxygen atoms in the compound CO2, and no subscript following the symbol C says only one carbon atom occurs in the molecule.

The lack of a number preceding the carbon symbol C and the compound formula CO2 shows that there is one carbon atom and one carbon dioxide molecule. Meaning of Subscript Numbers. Subscript numbers in chemical formulas represent the number of atoms or molecules immediately preceding the subscript.