A molecule of carbon dioxide (CO2) has a total of three atoms: one carbon atom and two oxygen atoms.
In chemical notation, ‘CO2‘ indicates that each molecule consists of one carbon (C) atom and two oxygen (O) atoms. The ‘2’ in the formula signifies that there are two oxygen atoms bonded to a single carbon atom. Therefore, to find the total number of atoms in one molecule of CO2, you simply add the number of carbon and oxygen atoms together: 1 (C) + 2 (O) = 3 atoms.