00:02
Hi there.
00:03
This question is asking about dipole -dipole forces.
00:07
Well, dipole -dipole forces are intermolecular forces of attraction, which means they attract molecules to each other.
00:17
And dipole -dipole forces are found only between polar molecules.
00:27
Let's see, between rather than in.
00:30
So it's only found between polar molecules.
00:35
So to identify which of these substances, is going to have dipole -dipole forces, we need to determine which ones are polar and which ones are non -polar.
00:46
So starting with br2.
00:49
That means we have vr bonded to a vr.
00:53
Well, there's no difference in electronegativity since they are the same.
00:58
So that's going to be a non -polar bond and give us a non -polar molecule.
01:04
Next we have cbr4.
01:08
Well, if we sketch that, we see that it is a tetral.
01:15
And it is symmetrical.
01:19
So even if the bonds are polar, the molecule itself is going to be non -polar because it is symmetrical.
01:27
So we have another non -polar molecule.
01:33
So neither of these will have dipole -dipole forces since they're both non -polar...