Learn about the stories behind 10 extraordinary inventions. In this video, you'll learn about white phosphorus.
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Philip Silverman: So, what we have here in the bottle is an oil bottle of yellow phosphorus, its really nasty stuff so we are going to be extra careful with it. We have a solid that we are going to use here carbon disulfide. We are going to take the white phosphorus out of the bottle, drop it into another bottle, the liquid that we used to keep this from oxidizing is water. We are going to take it, we are going to have a little bit in here, we'll chuck cut a piece off, put in the test tube. There is some carbon disulfide around it, so that's going to be solvent that's going to dissolve the white phosphorus, we are going to take that, put it on this piece of paper and see what happens. So, what I'm going to attempt to do is remove a piece of white phosphorus from this bottle and drop it into this smaller beaker, so we can then use it to dissolve it up. Nice big chunk of white phosphorus here, it's kind of waxy material. It's not the easiest stuff in the world to cut. We want to make sure to keep it under water at all times. Now, before we do that, we are going to take carbon disulfide, we have this already in the tube because we do not want to have the phosphorus sitting there being exposed to air. Because if we do that, it will immediately burst in the flame and that will be bad. We can transfer this safely because we still have a little bit of water on it. We'll take this, we will dissolve it up and we will get a lot of this phosphorus that actually go directly into the solvent. The solvent we are using is carbon disulfide and its smells really, really bad. Now, we are going to do is take a pipette, put a little of this material and as it dries it just start to oxidize. What does it shows us? Well, it shows us the reactivity of a pretty interesting material that is a highly reactive, we want to tend to be very careful about having this in our environment because as you are able to see just by a mere exposure to oxygen, this entire amount of stuff is able to within just a second or two completely burn this filter paper. So, if you are getting the stuff around you or on you, it can cause very, very rapid reactions that could actually completely engulf you in flame, so where burette is relevance to something you would find in your everyday life and would strike anywhere matches. You want to be careful with those because when those go those produce a whole lot of heat and they can rapidly oxidize those things around them and you don't want to be the thing that they are burning.