 What's the difference between a solid a liquid and a gas? Think of these balls as atoms or molecules and here we have a nice orderly structure as in a solid if we add energy The molecules vibrate But they stay in relative position. So they are there's kinetic energy their motion If we increase that kinetic energy and give them more Now we have a Let's suppose we have a liquid that is a mixture of two compounds Let the white golf balls represent ethanol and the blue Represent water and we want to separate them at this point. You see there are 18 White ethanol molecules and only four water molecules. So we're going to heat this up add energy to it So as we add energy Some of it is going to evaporate and leave our container All right after adding a little energy now we have two four six eight ten twelve White balls and four blue balls. So let's try again add more All right now you see there two four six Ethanol and three water molecules You should note that even though what we're trying to do is remove all the ethanol We also remove some of the water. So when you're trying to distill something, you're not going to get a 100% pure Substance You should be able to calculate the mole fraction by counting the number here. Let's let's try one more time All right. We're even more concentrated with water now. We have two ethanol's and three waters Would we're going to post the data from the four different Mixtures that we showed and we'd like you to calculate the mole fraction and the total pressure of each one