Which of the following is a hydrophobic material? a. paper b. table salt c. wax d. sugar

Video transcript

Hello everyone. So today's video is going to be about a very simple problem. So let's jump straight into it. All of the following are hydrophobic molecules except so before we start I want you to pay attention to these except term what is telling us is that we're not really looking for are hydrophobic molecule. Within our answer choices we're looking for the opposite which in this case is a hydrophobic molecules. And to help you remember the differences between hydra filic and hydrophobic molecules as well as help us classify each of the molecules that were given as hydra filic or hydrophobic. I've created this graph that will be using in the question. So now I want you to recall from Jason's videos on the topic what a hydrophobic molecule is hydrophobic molecule is nothing more than a water loving molecule which means that will interact very well with water. Some of the characteristics of these hydrophobic molecules is are there polar and charged? Moving on we have hydrophobic molecules which are going to be the opposite. They're going to be water fearing and will not interact very well with water. And the characteristics of these is that there will be non polar and on charge. So it'll be the opposite of hydrophobic molecules in order to solve a problem. Will be using the concept of hydra filic versus hydrophobic but I want you to also recall the concept of like dissolves like as it will be very important in classifying the molecules that we are given as hydra filic or hydrophobic. Now that we have established what we need to solve the problem. Let's move straight to the answer choices. So we can begin classifying each. Starting with glucose, glucose is a readily available carbohydrate molecule that humans and many other species use for energy. It is present in the cytoplasm of the cell, which is mostly composed of water. So we can already see that glucose is going to interact well with water since it's present in the same environment. Now, the reason why glucose is able to do this is because it has so many O. H groups and its molecular structure. This ohh groups make glucose extremely polar. And as we can see in our graph, polar molecules are classified as hydro phallic. So glucose is not the exception that the question is asking for and we will cancel it out. Moving on, we have cellulose. Cellulose is what we call a polymer molecule. Polymer molecules are very large molecules are created from repeating units of monomer molecules. In this case, cellulose is a polymer of glucose, so it will share many of the characteristics of glucose, including the fact that it is polar. So cellulose is also hydro filic molecule according to our graph and we can cancel it out as not being the exception. Moving on, let's talk about any cl or table salt. Now one should recall if you have ever put table salt in water. What usually happens is that it disappears very quickly. It dissolves very well in water. The reason for this is that table salt in water becomes any plus and cl minus. And these ions are charged charged species according to our graph are also hydro filic and will interact very well with water. So we can cancel out table salt as not being the exception to a question. This all leaves us with olive oil being or only possible answer choice. While I want you to recall what olive oil really ease, it is nothing more than a fat or a lipid. Specifically olive oil is what we call a triglyceride molecule. Triglyceride molecules are made up of a glycerol backbone and three fatty acid chains. These fatty acid chains are very long, they're very big and they're mostly made of hydrocarbons, which makes them non polar. So olive oil is overall a non polar molecule. And looking at our graph, we can see that non polar molecules are hydrophobic. And so this is why olive oil is our correct answer. So, thank you very much for sticking around until the end of this video. I really hope it helped you