Two dichloroethylene molecules with the same chemical formula 1C2H2Cl22, but different arrangements of atoms are shown.

(c) Which form of dichloroethylene has the highest boiling point?

Video transcript

Hello everyone today. We have the following problem. The following figure shows two molecules of the same chemical formula. We have the cIS and the trans the structure, so that the atoms and these two molecules are arranged differently determined which molecule has a lower boiling point. So the first thing we need to establish is that inter molecular forces are dependent or they determine many physical properties such as melting points and boiling points. And so with that we say that the stronger the inter molecular forces, the stronger the melting points and the stronger the boiling points. And so the strength of these forces is dependent on molecular polarity. So we should look at the polarity of these molecules. So a train on the periodic table is electro negativity in that states that as you go up the periodic table into the right of the periodic table, your electro negativity increases. So between the carbon and browning bond, we can say that browning is more electro negative. So for the cis they are on the same plane because they are both on a wedge. So the dipole moments are going to go from the carbon to the bombing. For the trans, however, they're on opposite sides. So while the dipole moments appear to be going in opposite directions, they're actually going or while they appear to be going in the same direction, they're actually going in the opposite direction. So we can say that the dyp holes in our transit result in a non polar molecule because the dye poles cancel each other out because they're going in opposite directions. This is going to be polar because the dye poles don't cancel out. I don't cancel out. And so we have to determine which has a lower boiling point. Well, since the system is more polar, it's going to have a higher boiling point. And subsequently our transit is going to have a lower boiling point due to it being non polar. So our answer, it's going to be the trans summer. And so with that we've answered the question overall, I hope this helped, and until next time.