And thus far, we've said that, according to quantum mechanics, the number of atomic orbitals that we're combining must exactly equal the number of molecular orbitals that we are forming. Once again, the number of orbitals you are combining must equal the number that you are forming. Now. So far, we have tried to combine the one s atomic orbitals of two identical H atoms. So they're both neutral. That means they have one electron and one proton each.