The critical temperatures and pressures of a series of halogenated methanes are as follows:

(a) List the intermolecular forces that occur for each compound.

Video transcript

Hey everyone, we're given the following data and were asked which statement is true and it looks like they want us to compare polarities and our inner molecular forces. So first let's go ahead and draw these out. Starting off with our bromo try chloral methane, our carbon is going to be our central atom and we will have a browning attached to it and three chlorine as we can see right here, our bromo trecorum methane is going to be polar and that's because we have our di pole moments pulling on each one so this experiences disciple disciple and London dispersion forces with like molecules. Now let's go ahead and draw our tribe Romo chloral methane again carbon is going to be our central atom and we will have a chlorine attached to it and three bro means similar to our bromo trecorum methane we do have these disciple moments and again this is also going to be polar. Now when we go ahead and draw out our tetra bromo methane, our carbon is going to be our central atom and we will have four bro means surrounding it, this will have a tetrahedron geometry which means it is symmetrical, so our disciple moments here will cancel out. So this means our tetra bromo methane is going to be non polar and since it's a non polar compound, this will only experience dispersion forces. Now let's go ahead and look at our answer choices. It looks like A is incorrect because it is stating that are bromo try chloral methane exhibits ion dipole forces which is incorrect. Next looking at b. It is stating that our tetra bromo methane exhibits ion dipole forces, which is also incorrect since we stated that it only experiences London dispersion forces. Next looking at sea, we have only try bromo chloral methane is polar and exhibits dipole dipole forces and London dispersion forces. Now we know that our tribe Romo claure methane is polar and it does exhibit these two forces, but it is not the only one. So she is also incorrect. And for D we have both Triboro chloral methane and bromo try chloral methane are polar and exhibit disciple disciple forces and London dispersion forces, which is correct. So it looks like D is going to be our final answer. Now, I hope that made sense. And let us know if you have any questions