Chemistry q here. I'm given the first ionization energies for "X" and "Y", but no units.

Question

Like I said, no units are given. It says it's going by the size of the "relative IP's", which I have no clue what that means exactly. We are supposed to provide answers for the elements X and Y. I'd appreciate any help!

X - 350 > 790 > 1250 > 14400 > 19250 > 3200
Y - 200 > 450 > 800 > 12500 > 15750 > 28500

Answer 1

The units for ionization energies are usually in kJ/mole, but you don't need the units to do the problem.

What you're looking for is a large jump in the ionization energy, which says that you're no longer ejecting valence electrons, but core electrons, and those take a lot more energy to get out. For X you get reasonably small numbers for the first three ionizations, then a sudden large increase. So the element has three VE's... Aluminum or another member of that group. Can't be B because you have more than 5 ionizations. The same thing happens with Y: you also have three VE's, so the element is also in the group with Al. The actual ionization energy values are all smaller than in X, though. That tells you that the electrons are further from the nucleus, i.e. that they're in a higher shell. So Y is beneath X in the group. You can't definitively identify the elements without looking up the actual numbers, but something like X = Al and Y = Ga, or X = Ga and Y = In would be reasonable answers.

Answer 2

This question is not answerable as it stands. I think you when your classmates together should approach the teacher, and ask what it is supposed to mean.