The structures of vitamins E and B6 are shown below. Predict which is more water soluble and which is more fat soluble. [Section 13.3]

Video transcript

Welcome back everyone in this example, we need to determine which of the following vitamins is water soluble and or fat soluble. So looking at vitamin D, we can see we have a very large molecular structure of hydrocarbons, recall that each corner represents carbon atoms and each of these carbon atoms should have four bonds where one of the bonds should be hydrogen. Now, comparing our electro negativity between the carbon atoms and hydrogen and these structures, we should recognize for example, this carbon atom is bonded to two hydrogen atoms which are implied, but we're drawing them in now and recall that carbon is more electro negative than hydrogen on our periodic table. So carbon is going to have that slightly negative dipole, whereas our hydrogen atoms will have the slightly positive di pole there. If we recognize that our electro negativity trend increases as we go towards the top, right towards flooring on our product table. What we just outlined will make sense and because we have these disciples throughout this entire molecule of vitamin D. Due to the presence of the carbon and hydrogen atoms that make up the structure, we're going to say that we have strong dispersion forces. Since this is again a long hydrocarbon chain and these dispersion forces are not going to be a match to be able to fight against the forces in our water molecule. Because we should recall that water has hydrogen bonding and recall that hydrogen bonding is a very strong inter molecular force. So we're going to need something even stronger than just dispersion forces, meaning that we can say that vitamin D. Is going to be fat soluble since it won't dissolve in water, it should dissolve a fat. And so this is going to be our first answer for vitamin D. Now we want to focus on vitamin C. And we should recognize that when it comes to vitamin C, we have a total of four alcohol groups which allows it to have a lot of the inter molecular force being hydrogen bonding. Since it has the presence of hydrogen, and this is a much smaller molecule. Since we have such a rich presence of the inter molecular force being hydrogen bonding, vitamin C should definitely be able to be dissolved in water. And so we would say that vitamin C is also, or in this case is going to be water soluble more than being fat soluble. And so for our final answers, we have that vitamin C is water soluble and vitamin D. Is going to be fat soluble. So I hope that everything I outlined was clear. If you have any questions, leave them down below and I'll see everyone in the next practice video