The electrons that are shown here in this actual ionization
energy graph, which again, I said came from a textbook.
This is not my graph, it's my friend Denis Wirtz's graph.
The actual ionization energies here are only for
the ones that are in the outermost shell.
There are other electrons for fluorine, for example,
fluorine doesn't have just five electrons, it's got
nine electrons.
So there's some lower energy electrons for fluorine down here, right?
In a 1S and a 2S orbital. And I don't have those drawn here.
Because, when it comes to the first ionization energy, the only
thing we care about is removing the highest energy electron of fluorine.
How much energy does that take?
Well, they've measured it.
And for one mole of fluorine, it takes 1,681 kilojoules
to remove a mole of electrons from a mole of fluorine atoms.
So I'm measuring this distance really.
Here's the distance up to the energy of zero, you see that?