Learn about Junior Chemistry, Solutions 3, in this comprehensive video by bannanaiscool.
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Okay, you’ve got yourself a beaker and inside the beaker you’ve got yourself a solution. If you could dissolve more crystals of say a solid into that solution or that solid to make a solution—putting more crystals and they totally dissolve, you have yourself a solution to begin with that was unsaturated. But if you can actually pour in enough crystal where there are some sitting on the bottom of the beaker in the end, and no matter how hard you stir they won’t disappear now your solution in here is saturated. It has got as much solute as the solvent can take at that given temperature. But if you raise the temperature you're probably going to be able to dissolve more solute in the solvent to make a solution. Now, this solution however, we say that even though it looks kind of static and nothing is happening, it’s actually at a point where the rate of crystals dissolving into solution equals the rate of recrystalization at the microscopic level. You can’t see but that’s what’s happening. That’s called equilibrium, when the rate of forward equals the rate of reversed process. Now, that’s a very important topic in senior advance chemistry and that’s coming up on subsequent discs. For right not, that is a saturating solution. But if you warm up the solution you can dissolve those crystals on the bottom and put them into solution and that will saturate it at a higher temperature. But what happens if you cool the solution back down to the original temperature? Do the crystals come out again? Not until you may be putting a little seed crystal into the solution and then recrystallization will occur around it. So what do you call a solution that contains more than the equilibrium amount of solute dissolved in the solvent? That’s called super saturated.