This video was produced by... This demonstration has safety risks. Because of these risks, we wear closed-toed shoes and safety goggles. This demonstration should only be done by a trained professional and should not be tried at home. Hi, I'm Kevin Karen and I'm coming to you today from the Chemistry and Biochemistry Department here at James Madison University. I'm going to show you a demonstration today called Super Saturated Sodium Acetate. Here I have a solution of sodium acetate and it's super saturated. Now what that means is that there is more sodium acetate in solution in water than the water could normally hold at room temperature. So if I tried to make this solution by dissolving solid sodium acetate in water at room temperature, some of the solid would not go into solution. We made this solution by warming up that mixture to allow everything to dissolve and then we subsequently let the mixture sit and cool slowly and if we're careful and if we're lucky which we were, the sodium acetate does not come back out. So we have this solution here and we've kept it covered with a beaker overnight so that no dust particles get in there because very small stimuli can actually start the crystallization process. So there are a number of ways that I can start crystals forming in this super saturated solution. This is a meta-stable non-equilibrium system and if I was to take a seed crystal like the one I have here, I've got a small seed crystal sitting on the table. If I was to take that crystal and put it into the solution that would serve as a template around which the molecules and solution would arrange themselves and start crystallizing around that seed crystal. Alternatively, I could even put a piece of dust in there that will often start the process. Even I could even just knock on the table hard enough and that will often start the process. What I'm going to do today is I'm going to very carefully pour the solution on top of the seed crystal that I have here on the bench and we'll see what happens. So as you see, the crystallization is happening around that seed crystal and if I'm very careful you can get this to pour into a nice column that crystal that I had down there was the trihydrate of sodium acetate, meaning that there are three molecules of water associated with each sodium acetate in that solid. So the solid that we're forming here is most likely also the trihydrate. Now the solution that we started with had about 5.2 molecules of water per molecule of sodium acetate. So it's possible that there is some higher hydrate forming. However, it's a little bit more likely that it's the trihydrate and the extra water molecules are just trapped within this structure but not actually part of the organized crystal structure. This is the nexothermic reaction so if I was to put my hand next to the column I would feel a little bit of heat coming out of this and I'm actually quite amazed that how tall this is getting. I've never ever ever seen one this high and I think we got it on video. See if we can get every last drop on there. There we go, super saturated sodium acetate. So we just saw a demonstration where we made a sodium acetate trihydrate column and we're going to try to crystallize this next super saturated solution by dropping a seed crystal in. So I have a seed crystal on the end of my spatula here. I'm going to drop it in and hopefully it will start the crystallization process. Here we go. Here we go. Pretty awesome. That was pretty fast. If we look in here we can see that all the crystals are emulating from a central point and that's exactly where I dropped the seed crystalline. Also I'm touching this with my hand now. The outside of the beaker is warm because this process was an exothermic process. So I'm going to show you this is the column that fell down a little while ago. This is a piece of our column. I'm going to just gently crush it with my hand. You can see kind of a brittle solid. I can just crumble it into this powder of the trihydrate. So we can actually take this solid, collect it, re-desolve it and do this experiment over and over again. So this can be used many times. There you go. Thank you very much. This is Kevin Karen. Have a great day.