 Okay, so we're going to determine the bond polarity between nitrogen and oxygen. So these elements on this, are these values on this table of electronegativity values are in units of divides, okay? So what you need to do is first figure out, well, what is the overall electronegativity of each of these two elements, okay? So nitrogen, all we have to do is look at the table and remember this table has to be given to you, it's not something you're going to memorize, okay? So nitrogen up here is what, can you guys see that? 3.0, okay, and it's 3.0 divides another capital D for you guys. And oxygen is what? 3.5 divides, okay? So if I want to determine the bond polarity and which direction the polarity arrow is described, what I do is just subtract one from the other. So here I got 3.0, 3.5, so the overall difference, right, is going to be 0.5. So we say the bond polarity, 3.5 divides minus 3.0 divides. So that equals 0.5 divides. Not a very polar bond will describe how polar you have to be to be a polar bond. So when we look at this, right, oxygen, since it has a higher number, is more electronegative, okay? So that means it attracts the electrons more. So this isn't a completely shared set of electrons in this bond. Does everybody understand what I'm talking about? So it's not a completely nonpolar bond. So we have to figure out, well, which way is, which atom has the more kind of concentration of electron density? And hopefully you see it's oxygen, right? So we can describe this in a couple of ways. Okay, I'm going to show you two right now. One is to go through the partial charges, and we call them delta charges. So this is delta minus and delta plus. Okay, so that's a way to describe the bond polarity. So this side of the bond is more negative than this side of the bond. Is everybody okay with thinking like that? Or you can draw a dipole arrow, okay, which is an arrow that points towards the more electronegative atom and that the butt of the arrow has a plus sign, okay? So the plus indicates which one is more positively charged and the head of the arrow indicates which one's more negatively charged. Is everybody okay with that? So if we wanted to, we could describe this type of covalent bond as a polar or a nonpolar. This case, since there's a difference in electronegativity, and in fact what you'll find, as you guys don't know this yet, but we're going to see it on the next slide, if your difference in electronegativity is more than .4, you say you've got a polar bond, .4 device, okay? So this one's .5 device, so this is a polar covalent bond, we would say. So remember electronegativity increases as you go up the periodic table and increases as you go to the right to the left of the periodic table. Is everybody okay with that? Okay, I'll see you guys upstairs.