A student was contemplating a question regarding elements with "no empty valence orbitals." An argument was made that elements all have infinite number of valence orbitals.
Every atom basically has an infinite number of shells. The thing is that almost all of those shells are empty (they don’t have electrons in them).
So it is facile to say that, say, the fluoride anion has no empty valence orbitals on the basis of it having 8 valence electrons and the $2n^2$ rule (where n = 2)?