 All right in today's video I want to talk about this realm within solutions known as solubility. So first of all what does it mean for something to dissolve or be soluble? Whenever something dissolves you make a solution. Now how do we determine if something is a solution or not? We first have to look and see if the if the item is transparent. All right all solutions are transparent. Now what a solution is it's where your particles are mixed at the molecular or the atomic level. Now you see down here we have a few figures. First of all we have apple juice. All right so apple juice even though it has color it is still transparent so that tells us that it is a solution. On the other hand something like milk. Milk not being transparent is not a solution meaning the particles that make up the milk are not mixed at that atomic level. Now what are the different parts that make up a solution? There are two parts that make up all solutions. First of all the solvent. The solvent is the larger of the two items. This is the part of the solution that does the dissolving or dissolves the smaller part. That's known as the solvent. The solute is the smaller of the two portions. This is the part that dissolves in the solvent. The solute is the smaller the solvent is the larger. Solubility is described as used is the term described the term we use to describe the amount of solute that dissolves in a specific amount of solvent and in chemistry we use solubility to tell how much of the solute dissolves in 100 grams of the solvent. An example of this is glucose. So glucose at room temperature or 25 degrees Celsius has a solubility of 91 grams per 100 grams. So what that tells us is that 91 grams of glucose will dissolve in 100 grams of the solvent in this case it's water. Next up let's look at some factors that either can inhibit or allow more solute to dissolve. What factors affect solubility? First of all being temperature. This one should be one that we all know of. As we increase the temperature of our solvent we will be able to dissolve more solute. Most items are more soluble at higher temperatures. Another factor is the type of solvent or the type of solute that can affect solubility. Pressure. Pressure can affect solubility as well. Henry's law looks at the effect of pressure on the solubility of gases in a liquid. And if you just open up a can of soda you will see that the gases that were contained within that liquid come out they become unsoluble. They will come out of solution which is what forms those bubbles that you see. And another factor that affects solubility is polarity. So we should know that polar solvents will mix with polar solutes. Nonpolar solvents mix with nonpolar solutes. Nonpolar and polar substances do not mix very well. That brings us to how much of a solute will dissolve in a particular amount of solvent. And this is known as saturation levels. We have three different types of saturation levels. The first being an unsaturated solution. An unsaturated solution has solvent that can continue to dissolve more solute. So for example we look back at our glucose. We said that the solubility of glucose at room temperature was 91 grams per hundred grams of water. So if we were to add 50 grams of glucose to 100 grams of water this would be considered an unsaturated solution because that solvent in this case the water can continue to dissolve more glucose. Another saturation level is the opposite of unsaturated or a saturated solution. In a saturated solution all of your solvent has completely dissolved the maximum amount of solute that it's able to dissolve. So an example of a saturated solution would be adding 100 grams of glucose to 100 grams of water. This solution has dissolved its full 91 grams of glucose and that last nine grams left over simply float to the bottom. A third condition which is not well known is known as a super saturated solution. In a super saturated solution the solvent has actually dissolved more solute than should be possible and this is a fairly unstable condition. Now how do we tell what type of solution we have? Is it unsaturated? Is it saturated or is it super saturated? We can test this using what we call the crystal test. The crystal test is simply adding one crystal of our solute to our solution that we want to determine if it's saturated, unsaturated or super saturated. What would we expect to happen if the solution is unsaturated and we add one more crystal of our solute? Well if it's unsaturated and that solvent can continue to hold more solute then that one crystal would dissolve. If it dissolves we know that our solution is unsaturated. Now what would we expect to happen if our solution is saturated? If our solvent has dissolved the maximum amount of solute that it can and you add another crystal that crystal will not dissolve so therefore it will simply float to the bottom. This is going to imply that you have a saturated solution. And then finally this super saturated solution if you add a single crystal of your solute to a super saturated solution since this super saturation level is so unstable what that crystal will do is it will cause a chain reaction which causes the excess solute that was dissolved to pretty quickly come out of solution and it will either crystallize or it will float to the bottom. So hopefully this video has given you a good idea of solubility and what it means for something to be soluble or not and how we determine the different soluble or saturation levels of our solvent.