In this video, we're going to continue talking about the properties of water, specifically how water can act as the universal solvent. Now, water is described as the universal solvent because water is capable of dissolving so many different types of solutes. And so we need to differentiate between the term solvent and solutes. The solvent is defined as the substance that does the dissolving, and usually the solvent is going to be found in larger amounts. When referring to life, usually the solvent is going to be water itself. Because water can dissolve so many different types of biological molecules, we call it the universal solvent. Now, the solute, on the other hand, is defined as the substance that gets dissolved by the solvent. Usually, the solute is going to be found in much smaller amounts. If we take a look at our image down below at our example, we can differentiate between the solvent and the solute. We're looking at an example of table salt or sodium chloride (NaCl) being dissolved in water. Notice on the left here we have our sodium chloride, the table salt, and on the right, we have the sodium chloride being poured into our water.
On the left-hand side, when we're just looking at the table salt, recall that it's made up of sodium chloride molecules where the sodium cation, which is positively charged, and the chloride anion, which is negatively charged, form ionic bonds. However, when we take the table salt and dissolve it in the water, the ionic bonds are disrupted, so the sodium cation is not capable of forming an ionic bond with the chloride anion mainly because the water molecules surrounding them are disrupting the potential for them to form ionic bonds.
Notice that the water here in this scenario is what is doing the dissolving. The water is going to be found in larger amounts; it's what's doing the dissolving and so the water is going to be the solvent. Therefore, this means that the solute is going to be the sodium chloride. The sodium chloride is what is getting dissolved by the solvent. When we take the combination of all of the solutes and the solvent, what we get is the solution. The solution is the combination of the solute and the solvent. Now, because water is acting as the solvent, we call this an aqueous solution. An aqueous solution is a solution in which water acts as the solvent.
Also, notice that the water molecules in the solution are going to form what's known as a hydration shell around the dissolved solute molecules. When we take a look at the dissolved solute molecules, the sodium and the chloride, notice that they are being surrounded by what is known as a hydration shell, where water molecules surround the substance and interact with the substance to dissolve them. This here really concludes our introduction to the lesson on how water acts as the universal solvent and can dissolve so many different types of solutes. Moving forward in our course, we'll talk about how water can dissolve most of the biological molecules that we'll discuss, such as proteins, nucleic acids, and carbohydrates. This concludes our lesson, and we'll be able to get some practice applying these concepts in our next few videos. So, I'll see you all there.