 How do you figure out if something's iso-electron? Same amount of electrons. Well, the same electron configuration is the better way to think about them. So there are things with, it's true. It is a better way to think about them. So, pardon me. When would be a fine word they don't have? Well, you know for a fact that there's some of those weird ones out there. So watch out for those. So the electron configuration may be different. So watch out, OK? Let's do the electron configuration. So CL minus. Help me out. 2, that's 2, 2B6, 3B5. 3B. Don't worry about that. What about that? Oh, I don't know what's happening. OK, so is that the right electron configuration? Yes. What about this one? Is this the same? Is it electronic? Yeah. Got it back there?