Where, approximately, is the negative pole on each of these molec...

Question

Where, approximately, is the negative pole on each of these molecules?

Accepted Answer

welcome back. So we need to identify the approximate location of the negative pole on each of the following molecules. And then we need to identify which molecule has a higher disciple moment and explain why So Higher dipole moment basically asking which one is more polar. Alright so let's take a look. So for both of these molecules it is implied that that middle right there is actually carbon, it's not written but it is implied that it's right there, right, I'm going to go ahead and just erase it. Just know that it's there. Alright so oxygen obviously is more electro negative than carbon, right? So it is going to be pulling electrons towards itself. So there's going to be disciple um arrow pointing towards oxygen because it's more electro negative but then we also have chlorine as more electro negative than carbon. So it's going to have its own Deibel and there's two of them, so it's going to be going this way. Now notice that the actual net disciple moment is going to be uh pointing towards oxygen. So this is going to be in the net right? So the approximate location of the negative pole on this molecule is going to be on the oxygen. So it's gonna be a bigger negative um poll on the oxygen because oxygen is more electro negative than chlorine. Let me fix that. It looks ugly. Okay, I can't draw that. Okay, so even though we do have chlorine pointing their diaper areas this this way. So um if you were to say what is the net dipole moment of both of the chlorine, it would be going down and then net depot for oxygen is going to go up. But then the net dipole moment on the whole molecule is towards the oxygen because oxygen is more lecture negative than chlorine. Okay so we're going to stay on the oxygen now for the next one. Again we have chlorine here. I'm sorry, we have carbon in the middle and oxygen is still more electro negative than the carbon. So it's going to be pointing that way. Um hydrogen is not very electro negative. In fact the bond between carbon and hydrogen is almost you know, there's such a small difference that it's insignificant. So we're not even going to take a look at that. But chlorine of course is still more electro negative than carbon. So we're going to go this way. So notice that the net disciple um moment on the on the full molecule is going to be kind of in between chlorine and oxygen. So I'm going to say the net so this is going to be nut. Okay, so the approximate location of the negative pole is going to be between chlorine and oxygen. So I'm gonna write partial negative here and that is going to be the sort of the approximate location. So it's not completely on oxygen. It's not completely and glory. But it's somewhere in the middle. Okay so now we need to identify which molecules more polar which one has a higher dipole moment. So we're looking at that net dipole moment. Okay, so C. O. C. L. Two because it has more mass. So that has nothing to do. But moller mass has nothing to do with whether you're more polar or not. Ah C. O C. 02 because it contains more chlorine atoms. So we're saying that this is more polar. Well if we take a look, it makes us a different color. If we take a look at the the net net the net but disciple of of oxygen and the net disciple of chlorine, they're kind of going in opposite directions. So even though they're not going to cancel each other out completely because they're still a net die po pointing towards oxygen, they nearly cancel each other out. Whereas here in the 2nd 1 in C O C. L. H molecule, we actually don't have anything canceling out where we don't have anything going in completely opposite directions. We actually have this going on here because of oxygen and chlorine. So like the net is kind of somewhere in between them. So we're going to say that the second one, this one is actually more polar. Now this one is more polar because it has a higher dipole moment because C. O. C. L. To the one on the left has some disciple disciple has bond typos that canceled its magnitude in a certain direction. So we're not saying that this is completely non polar and that they completely cancel out, but in certain directions, they kind of cancel out and make it a little bit less polar Than the 2nd 1. Okay, so options, see here is going to be a correct answer because again, the second molecule here has a net depot is going to have a larger net dipole moment because there's nothing canceling those two out as opposed to the first one. We have some cancelation here, and the net dipole moment is going to be smaller, so making it less polar. Alright folks, thank you so much for watching and let us know if you have any questions.

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Where, approximately, is the negative pole on each of these molecules?

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