 In this video, we're going to show you how to perform a vacuum filtration to filtrate, for example, the crystals we obtained in the recrystallization video or to separate solids from liquids in your reaction or in your washing steps. For a vacuum filtration, you will need a vacuum. And you can do this by either using a vacuum pump or using the vacuum pump that's in line in your fume hood. Besides that, you will need your filter, in this case a bugner funnel. And for the bugner funnel, you will require a filter paper that fits inside your bugner. You can collect the liquid in this filtration flask. And to make sure that you have a proper vacuum seal between the bugner and the filtration flask, you can use neoprene rings. During the filtration, you will need to clamp your filtration flask to the fume hood using a normal clamp. And besides that, you will of course need the solids that you want to filter. This is our crystals from the recrystallization video. Generally, you need to wash your crystals using a cold solvent that's the same as the solvent used during your recrystallization. And it's always handy to have a spatula at hand if you need it to get the solids out of your flask. Now that you have everything prepared for your filtration, we're going to build our filtration setup. So we place a clamp in the fume hood and attach it to the filtration flask to make sure that it can't tip over during filtration. In this case, we're using a lab jack to keep the filtration flask higher up. But you can also put it on the bottom of your bench. Now we're going to use the neoprene rings. And we just decide the neoprene rings that fit in your filtration flask and that fits snugly around your bugner funnel. And you can place it in the filtration flask. Place your filter paper on top of the bugner and make sure that it's correct size to cover all the holes and connect the filtration flask to the vacuum. In this case, we're using the inline system of this fume hood, but you could also use a vacuum pump that is available on most labs. Make sure it's attached tightly. This one has a screw cap. You can also have ones with opening where you just push the grey hose inside the filtration flask. Pour from the right, I guess. Now that we've built our setup, we can apply a light vacuum by either turning on your pump or turning on the inline vacuum system. And you should hear a small flow of air. And then you can pour your solids with its liquid on top of the filtration. Make sure to do this carefully so that none of the solids can actually go underneath your filter paper. And I already noticed now that these solids are very stuck in my flask, so I'll use my spatula to release them, at least I will hope. Demonstration purposes, I will not use all the solids. And we have here some ice-cooled water to rinse the solids of any remaining motor liquid of our recrystallization, to get pure crystals. Now that we've rinsed our crystals on the filtration paper, we can leave it drying under a small vacuum or an air, but please make sure to remove your liquid from the flask in the bottom, because with a small vacuum, this will evaporate over time and we don't want it. When your crystals are dry, you can continue with the rest of your experiment and analyze them for purity and melting point. This is how you perform a vacuum filtration.