The simple answer is 8 neutrons. But this depends on which oxygen isotope you are talking about. Oxygen-16, the most abundant oxygen isotope, has 8 neutrons.
8 protons, 8 electrons, 8 neutrons in oxygen
one neutron '
oxygen
Oxygen
oxygen atom has 8 protons and 8 neutron's. since they 8 protons they also have 8 electrons in there neutral state.
Formula of heavy water is D2O. O is oxygen, D is deuterium - a hydrogen isotope having 1 proton and 1 neutron.
Oxygen-16 and oxygen-18 are both isotopes of oxygen, differing primarily in their neutron count. Oxygen-16 has 8 neutrons, while oxygen-18 has 10 neutrons. Although both isotopes have the same number of protons (8), the difference in neutron count affects their atomic mass and some physical properties, but not their chemical behavior, as they both participate in the same chemical reactions.
300 :)
121
2
That would be a gas with the Atomic 8 and mass number of 16 - Oxygen
7 neutrons + 8 protons = mass number of 15