Which of the substances has polar interactions (dipole–dipole for...

Question

Which of the substances has polar interactions (dipole–dipole forces) between molecules?

Accepted Answer

What's up? Everyone in this video we're identifying which compound has type A type of forces being the strongest inter molecular forces present. Now, if you guys recall, we have four different types of inter molecular forces. The weakest of the mall will be London dispersion. The second biggest will be typo typo. Then we have hydrogen bonding and lassie will have ionic bonds or ionic bonding. So the question is asking us for depot, depot. So whenever we have dipole dipole, we will also have the molecule having London dispersion. So we'll cancel out these two. Alright. Starting off with A We'll go ahead and draw the lewis structure but before we're able to successfully draw the Lewis structure, we have to calculate the total number of valence electrons. So we have four bro means here. So brahman is in group 78. So there's going to be seven fans electrons per bromine atom Because we have four of those will multiply the number by four Giving us 28 valence electrons. And then we have one carbon carbon is in group four A. So there's going to be four valence electrons per atom two multiplied by one. Give us four. And these two numbers up we get a total of 32 valence electrons. You're drawing the lewis structure. We have carbon Connected to four Romans now filling in those long pairs. All right. So we can see that this molecule is actually symmetrical. So it's going to be non polar and because it's non polar, it will only display London dispersion. So A is canceled. Next we have B A. L. C. L. Three. So aluminum has three valence electrons florian has seven seven times three. This 21 Adding up to a total of 24 valence electrons drawing the lewiS structure. We have aluminum being the central atom Connected to three chlorine means and of course, don't forget your long piers. All right. So, this overall molecule is definitely non polar because it's very symmetrical. However chlorine and aluminum share a polar bond but overall this molecule is still going to be non polar. So be will also be eliminated. All right. Next we have a seat. So oxygen is in group 68. So, there's six valence electrons per atom. We have to so that's 12 oxygen likes to have two bonds. So draw the lewiS structure like this and fill in those thumb pairs. Alright, again, just like be this molecule is symmetrical. So it's definitely going to be non polar. So, C will also be eliminated from answer choices. Next we have the so D. We have nitrogen being in group 58. So that's nitrogen. And then we have Total of five higher regions. So one times 5 for the higher regions. And then we have one carbon which is in group four a. So there's four base electrons. Now I these valence electrons up. So we have five plus five Plus four giving us a total of 14 valence electrons. The lewiS structure will look like this. All right. As you can see here that the nitrogen is connected to hydrogen. That is hydrogen bonding. It's over here. So because we have hydrogen bonding present, it means that hydrant bonding will actually be the strongest inter molecular first present. So you will also be eliminated. And as by default, E will be your answer choice. Alright guys, thank you guys so much for watching and I hope you guys have a great day.

Struggling with General Chemistry?

Which of the substances has polar interactions (dipole–dipole forces) between molecules?

Watch next

Intermolecular Forces practice set