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- Solutions 32

Predict the geometry of each atom except hydrogen in the compounds below:

Hey guys. So in this problem we need to go ahead and figure out the geometry for all the non hydrogen atoms in this molecule, okay? So I'm going to go ahead and label them, a, b, c, and d, okay? So, let's sum with the easiest ones first. B, b is the easiest because it doesn't have any double bonds, no charges, right? If we look at this one over here, up a little bit, we've got an oxygen with three bonds, a lone pair and a positive charge, right?so, b is definitely the easiest one to start with, if we look at b, how many groups does it have on it? 1, 2, 3, 4, right? So guys, what's its hybridization going to be? It's sp3, right? That a little bonus, but what's its shape going to be, what's it's geometry, it's going to be tetrahedral, okay? Now, what about c? Well, c has a double bond, right? But look, it's connected to one carbon, another carbon and a hydrogen, so three groups total, right? Which means that's it's sp2 hybridized but guys, what's its geometry? It's going to be trigonal planar, okay? What about d? Wait a minute, d is exactly the same as c, right? It's connected to one carbon and two hydrogens, so we still only have three groups, so it's also going to be trigonal planar, but what about a? If we look at a now, hold on a second, we see an oxygen with three bonds and a charge, right? A positive charge, it's not very happy. Guys, if it's got three, if it's got three groups, right? Does it have three groups? Actually no, it's got four, that lone pair is a fourth group, right? Don't forget that, so guys, is it going to have a tetrahedral geometry? No, what it's going to have is a trigonal pyramidal geometry. Alright guys, let's move on.