December 12, 2003
At this time there was much talk on sciencemadness about the possibility of making sodium metal through a thermite type reaction and some members had succeeded in making very small amounts. I decided to give it a go with potassium hydroxide in place of sodium hydroxide though because I had read that the reaction of sodium or lithium hydroxide with magnesium metal could be very violent (as other members later learned).
The picture above was taken after the very fast but not explosive reaction with magnesium turnings (made from a large piece of magnesium, a drill, and some elbow grease). Ignition after applying heat with a torch to the bottom of a tin can was fast, the reaction:
2KOH + 2Mg ---> 2K + 2MgO + H2
Produces hydrogen, initially the lid of the can was lowered to prevent oxygen from getting in to a large degree, but very quickly hydrogen rose from the can, ignited, and blew the lid off, the mixture itself shot purple flames into the air. After nearly a minute of reacting I was left with the mass show in the picture above. When prodded or blown on it ignited giving off purple flames or merely glowed purple. The whole can after being allowed to cool was slammed upside down on the table, a large gout of purple flame rose up from it creating a spectacular scene and quickly died down. The solid left on the table combined with water with the evolution of gas, being as how potassium burns in air to make mainly the superoxide KO2 which reacts with water producing oxygen gas this is no surprise.
A vessel better able to exclude air with the option to distill would be perfect to get this reaction to work better. Potassium does not alloy with steel so it would be possible to make a metal reaction vessel with steel wool in one chamber, the potassium condensing out on it and once complete the steel wool could be removed and heated in an inert solvent, the potassium melting and sinking to the bottom allowing the steel wool to be removed.
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