Which of the following is a hydrophobic material?a. paperb. table...

Question

Which of the following is a hydrophobic material?a. paperb. table saltc. waxd. sugar

Accepted Answer

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 hydrophilic molecules except. So before we start, I want you to pay attention to this except term. What it's telling us is that we're not really looking for our hydrophilic molecule within our answer choices. We're looking for the opposite, which in this case is a hydrophobic molecule. And to help you remember the differences between hydrophilic and hydrophobic molecules, as well as help us classify each of the molecules that we're given as hydrophilic or hydrophobic, I've created this graph that we'll be using in the question. So now I want you to recall from Jason's videos on the topic what a hydrophilic molecule is. A hydrophilic molecule is nothing more than a water loving molecule, which means that will interact very well with water. Some of the characteristics of these hydrophilic molecules is that they're polar and charged. Moving on, we have hydrophilic molecules, which are going to be the opposite. They're gonna be water fearing and will not interact very well with water. And the characteristics of these is that they will be nonpolar and uncharged, so it will be the opposite as hydrophilic molecules. In order to solve our problem, we'll be using the concept of hydrophilic 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 hydrophilic 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 Oh groups in its molecular structure. These Oh groups make glucose extremely polar. And as we can see in our graph, polar molecules are classified as hydrophilic. 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 that 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 a hydrophilic molecule according to our graph, and we can cancel it out as not being the exception. Moving on, let's talk about NaCl or table salt. Now I want you to 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 Na+Cl- and these ions are charged. Charged species, according to our graph, are also hydrophilic and will interact very well with water, So we can cancel out table salt as not being the exception to our question. This all leaves us with olive oil being our only possible answer choice. Well, I want you to recall what olive oil really is. 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 3 fatty acid chains. These fatty acid chains are very long, they're very big, and they're mostly made up of hydrocarbons, which makes them nonpolar. So olive oil is overall a nonpolar molecule. And looking on our graph, we can see that nonpolar 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.

Which of the following is a hydrophobic material?a. paperb. table saltc. waxd. sugar

Key Concepts

Hydrophobicity

Polarity

Examples of Hydrophobic Materials

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