atomic mass is determined by the number of protons and neutrons
atomic_mass is not mass. equivalent is atomic_mass. atomic_nucleus is microscopic_object. neutrons has about_as_much_mass_as_protons hydrogen_atoms has one_proton_and_one_electron neutrons has not about_as_much_mass_as_protons atomic_mass is mass. hydrogen has atomic_number_of_one protons is component_of_atoms. atoms has mass