To determine the total number of atoms in a molecule, you need to consider the chemical formula and the subscripts associated with each element. In the case of 8O2, the subscript "2" after the oxygen (O) symbol indicates that there are two oxygen atoms in the molecule.
To calculate the total number of atoms, you multiply the number of oxygen atoms (2) by the coefficient in front of the chemical formula (8):
2 (oxygen atoms) x 8 (coefficient) = 16
Therefore, in 8O2, there are a total of 16 oxygen atoms.