Working With the Alkali Metals

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Has anyone ever worked with the Alkali Metals? I have some Lithium, Sodium and Potassium that I received a short time ago. I want to do some unique experiments and put them on YouTube I am familiar with what they are and of course I will take all safety precautions handling them.

The only thing I can think of is with the Potassium, don't even handle it with gloves on, it can spontaneously combust when exposed to open air. Otherwise, I'm hoping you're storing it in oil or some other dry environment.

Now if you're looking for some fun, make a paper boat and put some Potassium in it, put it in a pond/tank of water, and watch it eventually burst into flames and sink.

When I purchased the Potassium, it was sent in a bottle of mineral oil. Can you use vasolene to store Potassium?

No. Vaseline won't work since it won't isolate it from the air fully. You should only use lab-grade mineral oil to store elemental alkali metal. It must also be in an air-tight container. Best to store usually in the container it came in, unless it is otherwise specified not to.

It must remain isolated from air (oxygen) and water vapor in the air, and especially liquid water. Potassium burns on contact with water. Do not handle with your bare hands, it will react with the water in your hands.

You can cut the potassium using a regular stainless steel knife, but only cut under oil.

Agreed on everything the previous person said. My chemistry teacher in high school once set his sleeve on fire while demonstrating some Potassium. He was spreading it (it's extremely malleable) on some paper towels, hanging them from a ring stand, and spraying water on them to set them on fire, when the stuff he was spreading reacted spontaneously with the air and burst into flames. Took him a few seconds to realize he was on fire.

Another thing to beware of with Potassium: You must try to remove the storage oil from it before putting a piece into water or it can react with the oil creating an explosive compound. I did some demonstrations of group I and group II elements to school kids years ago and neglected to wipe the potassium properly and after flying around the trough of water on fire for a few seconds it exploded and jumped over the top of the safety screens and landed between the students and burned a hole in the floor! While all the kids were wearing safety glasses, had a piece of burning potassium metal landed on top of their head the consequences could have been... serious.

Also the piece of potassium was perhaps too large also. Aspies don't tend to do things by half!

I also demonstrated burning magnesium ribbon and for extra effect plunged a large burning length into pure oxygen. The FLASH was substantial to say the least. Nobody could see for five minutes!

The kids loved my chemistry demonstrations. I also demonstrated (outdoors) the old thermite reaction used to weld things. After the pool of iron had cooled one of the kids took the ingot of iron as a trophy.

Chemistry can be really exciting with some good spectacular experiments, and hopefully it encouraged the kids to study better or maybe even study it at university. Chemical equations can be very dull. Showing some of them in action adds that spark of interest.

Just be careful!

Yeah, but cut a (small) chunk off from time to time and throw it into a puddle of rainwater - at night. Around the new moon is good.

Apart from that, there's not a lot it's good for, is there?

If you are going to experiment with alkali metals always wear safety goggles and a protective apron,
Start with the smallest quantities first....Lithium is the least reactive with Cesium the most reactive...
Cesium is pyrophoric, it ignites upon contact with air. You might want to check out some of the reactions
described in Pop-Sci's Gray Matter

The alkali metals going up in reactivity are: Lithium, Sodium, Potassium, Rubidium, Caesium and Francium. The ones in bold are the ones I’ve seen dropped in water as part as a science lesion. Lithium fly’s round on the surface fizzing, Sodium does the same but more violently and Potassium sets off a purple fire, sends sparks everywhere and explodes. Rubidium, Caesium and Francium were way too dangerous to test and apparently would of ‘removed’ half of the classroom.

Francium is radioactive and shortlived, half life of the longest isotope is about 20 minutes so I doubt if it will ever be possible to get a lump of it to throw in a bucket of water. I always thought that Fr was a metal which no human has ever seen becuase it is so shortlived.

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Diagnosed under the DSM5 rules with autism spectrum disorder, under DSM4 psychologist said would have been AS (299.80) but I suspect that I am somewhere between 299.80 and 299.00 (Autism) under DSM4.

my guess is the oil caught fire due to the potassium reacting with the water. Oil is flammable, after all.

And also, remember that it is still not safe once it has completed burning. The potassium reacted with water becomes potassium hydroxide, which is a caustic base. If you use enough water, it will not be so basic, but the pH is still high enough to consider the waste water hazardous.