 Let's record the formation of the compound made from I don't know phosphorus and I have Okay, so first thing we need to do is draw the Lewis structures of those two atoms. Okay, so phosphorus Lewis structure remember dot So five a once right one two three four five So how many can bonds gonna make? three So iodine how many valence electrons does it have? Seven right, so we'll draw one two three four five Six Okay, so If I bond this with this does that fill up everybody's valence? No No, so how many more iodine's do you guys think? Why because iodine makes how many bonds? One and phosphorus makes how many bonds? Three okay, so you're gonna need two of our three of those items And now what we do is draw what we call a dish of arrows promotion of one electron and we make this compound called phosphorus tri iodide I'm just going to turn it over. It's best to keep your valence electrons there Hopefully you guys drew a picture similar to that So this is called a Lewis structure the Lewis structure of the molecule phosphorus tri iodide It does not actually look like this. Okay, it's not a tee It's actually what we call trigonal pyramidal So that means three-cornered pyramidal trigonal Parade So why is why does it look like that instead of like a tee? because those electrons want to be moved as far away from each other as possible and Vesper theory States that because they're negatively charged, right? They don't like to be in the same area as each other You got to negatively charge things kind of bouncing away Now it may seem that they're as far away as they can be in this In this drawing already, but recall this is a drawing on a two-dimensional plane. Okay, not on on three-dimensional surface like an atom or a molecule so in order to adjust for that we have to recall that they are spears atoms and We draw phosphorus tri iodide We're going to draw showing relative direction of those bonds so This is trigonal pyramidal. So if you can see right so any bomb That's just a straight line. That means that it's in the plane of the board any bomb that's A hashed line means it's behind the plane of the board and any Bond that's a wedged line means it's in front of the plane of the board What we will learn and we don't very much time right now, and I know we're just introducing this topic And it's how to Figure out what the bond angle is so we already said that this is a Trigonal Paramount structure you should be able to tell what the bond angle is and I go no you guys haven't memorized them yet But and this won't this case this one is one of seven point three Okay, so there's these numbers that you're going to have to memorize that's one We're going to start Next week just building structures building structures building structures. That's okay. Are there any questions on this one probably a bunch, but Probably nothing you guys can ask me right now, right?