Oxygen (O) has an atomic number of 8, which means it has 8 electrons in its neutral state. When two oxygen atoms combine to form an oxygen molecule (O2), they share electrons to form a stable molecule.
In the O2 molecule, each oxygen atom contributes 8 electrons, making a total of 16 electrons. These electrons are arranged in molecular orbitals, with the outermost electrons participating in the covalent bond that holds the two oxygen atoms together.
So, the O2 molecule contains a total of 16 electrons.