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So this is just to purify some manky white phosphorus to get a nice element that we know is

100% phosphorus which we can then use to fill the nanotude with.

In a lab at UCL, postgraduate student Martin Hart is gently warming some phosphorus in a flask under vacuum.

We can heat the old stuff and then condensing it onto a cold finger.

This gives us a lovely covered cold finger of incredibly pure white phosphorus.

So this liquid nitrogen which we use to cool down the finger and allow the

sublimation of the phosphorus onto the probe. The phosphorus sublims, it vaporizes, and then sticks to a gloss surface, the cold finger,

that is cooled with liquid nitrogen. What he's talking about is purifying one of the most dangerously

flammable materials ever discovered,

white phosphorus.

So we can just kick this along a little bit of heat.

The result is a white solid that will ignite instantaneously if it meets air.

This is chemistry at its most extreme, the chemistry of one of the strangest elements in the periodic table. I am Andrea Sahela, Professor. of This is my lab and I want to tell you about phosphorus and the extraordinary contributions it has made to our lives, to our wars and to our politics.

You can start to see it very faintly starting to supply them from the walls of the vessel onto the

probe which is being caused by the liquor nitrous.

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