 Okay, so in this problem, we're going to predict from successive ionization energies what the element is. So we have it all written down here in megajoules per mole, and it's a period two element. So the first thing we're going to have to do, and remember this is more of a qualitative type thing, so you're just looking at these numbers, you're going to have to find where the big jump is, okay? So I'm going to point, and you guys say yes when I get to the big jump. Pardon me. Okay, so there. Okay, so we've gone through six ionization energies, okay? So this is a period two element, we have to keep all that in mind. Okay, so let's just draw the ionization energies using x, just a whatever. Okay, so first ionization energy, we're going to get x. We're going to get x plus, right? Second ionization energy, x two plus. Third ionization energy, x three plus. Fourth ionization energy, and we're going to six. X four plus. Fifth ionization energy, x five plus. And then six ionization energy, x six plus. Okay, so now we look at the period two elements, and we count backwards to whatever would be the noble gas underneath it. So whatever would be the same electron configuration is a heli, right? So if we look, and hopefully everybody has done this already, it's oxygen, right? So oxygen has, when we go backwards, one, two, three, four, five, six, and we get to heat, right? So let's just confirm this by drawing the electron configurations of these things, okay? So remember, they have to be isoelectronic these things, okay? So what's the electron configuration of helium, which is the noble gas below period two? Helium, one s two, right? Okay, so what's the electron configuration of oxygen? It's one s two, two s two, two p, one, two, three, four, right? Four, okay? So to get to the electron configuration, one s two, how many electrons do we have to lose? Six. Six, right? Did we do that? One, two, three, four, five, six. Is everybody okay with that? So what did we get? We got oxygen six plus. What's the electron configuration of that ion? One s two. One s two, is that isoelectronic with helium? So then this is that element, okay? Is everybody okay with this? So this is how you identify an element from successive ionization energies. You have to know what period the element is on, okay, in order to do this. Questions on this thing? Okay, good.