Sciencemadness Discussion Board

Hand vs. NaK

EliasExperiments - 8-3-2021 at 09:45

I have made a video about a couple experiments with the explosive liquid metal NaK:

https://youtu.be/ESHuAJ01aJo

Does anyone have any other cool experiments, that I could perform with this stuff?

Amos - 8-3-2021 at 16:19

Experiment sounds like a pretty gracious term to assign to "Hand vs. NaK"

Furthermore I'm not sure chemistry enthusiasts are going to recommend the kind of content you stock your channel with.

j_sum1 - 8-3-2021 at 16:59

I kind of enjoy your large format stuff. But I can easily conceive of it all going wrong. That splash to the face was a warning.

But I agree with Amos. This is not a channel I recommend to my students. And it also seems a bit wasteful.



My view: keep doing what you enjoy. And continue to get views from people who do enjoy this stuff. But do stay safe. There are a few times that your safety margins have been a bit tight.

Sulaiman - 9-3-2021 at 01:52

I enjoy your videos - subscribed and liked

A face shield is a good idea.

Elemental Phosphorus - 9-3-2021 at 05:25

Will it form alloys with other elements? I wonder if you can dissolve lithium in a hot mixture of NaK.

Also, I'd be curious to see if it can form alloys with any non-alkali metals as well. Another interesting possibility would be to try and form a mercury alloy or maybe use some of the NaK to distill cesium metal off from cesium chloride and then combine more NaK with the cesium to make a very low-melting alloy.

Just some ideas.

But of course they would require many more safety precautions.

EliasExperiments - 11-3-2021 at 10:03

@Amos I guess it was almost certainly an experiment, because I don't think anyone has tried this before. At least not on YouTube.

@j_sum1 I don't think what I am doing is a lot more dangerous than driving a car for example. As long as I focus on what I am doing I am pretty confident that I can do it safely. I also can conceive of many ways how it can go wrong, but that it good, cause it helps me to avoid those ways.
If you have any suggestions on how I can make what I am doing even safer I'll be happy to hear them!

@Sulaiman Thank you and yes you are right. Next time I work with something explosive I will buy one first.

@Elemental Phosphorous. Yes you can dissolve lithium in it. That might indeed make for some really interesting experiments. I wonder if you can use that to make sodium that makes an even louder bang. That wouldn't be very scientific, but it certainly would be a lot of fun. XD Using NaK to make cesium is relatively difficult, because the difference in boiling point is low relatively speaking. But I have enough lithium to make cesium, I just need a suitable distillation apparatus.
I don't think cesium is really more dangerous than NaK, but I have never worked with it yet. I guess I figure that out once I get there.
Thank you for the suggestions!

itsallgoodjames - 11-3-2021 at 10:27

Quote: Originally posted by EliasExperiments  
@Amos I guess it was almost certainly an experiment, because I don't think anyone has tried this before. At least not on YouTube.

@j_sum1 I don't think what I am doing is a lot more dangerous than driving a car for example. As long as I focus on what I am doing I am pretty confident that I can do it safely. I also can conceive of many ways how it can go wrong, but that it good, cause it helps me to avoid those ways.
If you have any suggestions on how I can make what I am doing even safer I'll be happy to hear them!

@Sulaiman Thank you and yes you are right. Next time I work with something explosive I will buy one first.

@Elemental Phosphorous. Yes you can dissolve lithium in it. That might indeed make for some really interesting experiments. I wonder if you can use that to make sodium that makes an even louder bang. That wouldn't be very scientific, but it certainly would be a lot of fun. XD Using NaK to make cesium is relatively difficult, because the difference in boiling point is low relatively speaking. But I have enough lithium to make cesium, I just need a suitable distillation apparatus.
I don't think cesium is really more dangerous than NaK, but I have never worked with it yet. I guess I figure that out once I get there.
Thank you for the suggestions!


Cesium is more dangerous than NaK. If you make/get cesium, make sure to store it in proper low-oxygen mineral oil. It will react with baby oil, something NaK will not do.

chornedsnorkack - 12-3-2021 at 10:56

Quote: Originally posted by EliasExperiments  

@Elemental Phosphorous. Yes you can dissolve lithium in it. That might indeed make for some really interesting experiments. I wonder if you can use that to make sodium that makes an even louder bang. That wouldn't be very scientific, but it certainly would be a lot of fun. XD Using NaK to make cesium is relatively difficult, because the difference in boiling point is low relatively speaking. But I have enough lithium to make cesium, I just need a suitable distillation apparatus.
I don't think cesium is really more dangerous than NaK, but I have never worked with it yet. I guess I figure that out once I get there.
Thank you for the suggestions!

Li would dissolve poorly. Even in molten Na:
https://sites.google.com/site/catcalcphase/metal/li/li-na
Solubility in K is even worse, and NaK is mostly K.
https://www.metallab.net/chemsoc/alloys.php?id=3
there is Ftlite - Li-K, but it is implausible for lack of boiling lines.

[Edited on 12-3-2021 by chornedsnorkack]

EliasExperiments - 15-3-2021 at 10:38

@itsallgoodjames that sounds over simplified to me. Yes cesium ignites in air. But NaK explodes much more violently in water if compared on a gram by gram basis. If Cesium reacts with baby oil really depends on the baby oil, but I guess it will most likely react with contaminants in there same as NaK.

@chornedsnorkack Thank you for the interesting data! Well it might not be too soluble, but for lithium a little bit can go a long way. I still might try it though. Also I can't really imagine liquid Na and Li phase separating in a sense that it forms two layers. But if it actually does that might look really fascinating.

itsallgoodjames - 15-3-2021 at 10:45

Quote: Originally posted by EliasExperiments  
@itsallgoodjames that sounds over simplified to me. Yes cesium ignites in air. But NaK explodes much more violently in water if compared on a gram by gram basis. If Cesium reacts with baby oil really depends on the baby oil, but I guess it will most likely react with contaminants in there same as NaK.

@chornedsnorkack Thank you for the interesting data! Well it might not be too soluble, but for lithium a little bit can go a long way. I still might try it though. Also I can't really imagine liquid Na and Li phase separating in a sense that it forms two layers. But if it actually does that might look really fascinating.

From my experience, NaK won't react with scented baby oil

chornedsnorkack - 16-3-2021 at 09:15

When does baby oil react with KO2?
All simple alkali metal oxides, peroxides and hyperoxides are denser than the metals and therefore sink in the metal. Does KO2 sunk in bottom of NaK react quietly into K2O as it sinks, or does it accumulate and go off after induction period or setting off?

EliasExperiments - 16-3-2021 at 10:24

@chornedsnorkack I don't have the slightest idea. Reactions like that take literally ages to happen. But I have heard and read that KO2 and K metal is a dangerous combination. I guess if you mix the two and punch it like I did with the sulfur and iodine it might very well go bang.

@itsallgoodjames I mean what do you mean with react? My mineral oil was colored yellow after the potassium metal was in there for a couple of weeks. I have no idea why. Also when I first put the potassium metal or NaK in it bubbled a little bit from the water contained in the oil.

chornedsnorkack - 17-3-2021 at 01:20

Quote: Originally posted by EliasExperiments  
@chornedsnorkack I don't have the slightest idea. Reactions like that take literally ages to happen. But I have heard and read that KO2 and K metal is a dangerous combination. I guess if you mix the two and punch it like I did with the sulfur and iodine it might very well go bang.


And my point is that you donĀ“t have to do anything to mix KO2 with K. Since KO2 is denser, it simply sinks in bottom of liquid NaK and forms mixture of precipitate and liquid NaK between the precipitate grains.
How sensitive is it?
Does the precipitate defuse itself by quiet reduction to K2O, or does it stay explosive for a long time?

EliasExperiments - 18-3-2021 at 10:17

I doubt the KO2 will simply sink to the bottom, because the NaK has a very high surface tension, so it won't simply let something go inside it. I also doubt that KO2 and NaK react at room temperature without any outside influence, because the mineral oil will make it very difficult for them to meet each other that they can react. So I guess there is a very real danger of KO2 accumulating and exploding as soon as you mess with it again.

unionised - 18-3-2021 at 10:49

Quote: Originally posted by EliasExperiments  
I am pretty confident that I can do it safely.

That's the response you would have got if you had asked anyone about what they were doing, just before it went wrong.

Deathunter88 - 18-3-2021 at 11:49

I feel like this has as much "experimentation" as a lot of other bottom of the barrel viral youtube videos. (You know what I'm talking about, those that are like "EXPLOSIVE Sodium in GASOLINE" and then they act surprised when it doesn't do anything). At least have some semblance of following the scientific method, which although might not grant you as many views, would probably make your channel appear more favorable in the eyes of the amateur chemistry world. Two paths for you to choose, the easy mix everything together and see what happens route, or the more difficult but rewarding one.

chornedsnorkack - 19-3-2021 at 12:41

Quote: Originally posted by EliasExperiments  
I doubt the KO2 will simply sink to the bottom, because the NaK has a very high surface tension, so it won't simply let something go inside it. I also doubt that KO2 and NaK react at room temperature without any outside influence, because the mineral oil will make it very difficult for them to meet each other that they can react.


This depends on what wets KO2 preferentially.
If KO2 is preferentially wetted by NaK then the high surface tension of NaK simply pulls in KO2 grains. If, however, the oil wets KO2 better then the surface tension does keep KO2 on surface until the clumps build up sufficient thickness to break through NaK surface tension and sink to bottom, with an oil film wetting to them.

EliasExperiments - 20-3-2021 at 09:37

@unionised Well if you have any suggestions on how I can impove safety, I'll be happy to hear them :-)

@Deathunter88 Well you are certainly right that this was not my most scientific video. If you don't like it that is 100 % fine with me.
If I did anything that was actually against the scientific method please elaborate and I will try to avoid that in the future.
"Mix everything together and see what happens route" on the other hand sounds a bit overly simplyfied. I am not doing that stuff from the perspective of a child you never learned anything and just wants to blow stuff up.
I actually do have formal education in chemistry and I am right now finishing my masters degree. So I kinda know what I am doing.
Also I won't do anything just so I can appear more favorable in someone elses eyes. The most important priority for me is that I enjoy what I am doing. Only after I figured that out I think about how I can make it interesting.
If on the other hand you have some precise or concrete feedback on how I can improve my videos, I would love to hear it!

@chornedsnorkack Only one way to find out I guess. Buy some KO2, sprinkle it on the NaK and wait. If nothing happens try playing with it until it exlodes. XD

chornedsnorkack - 20-3-2021 at 11:32

Quote: Originally posted by EliasExperiments  
@chornedsnorkack Only one way to find out I guess. Buy some KO2, sprinkle it on the NaK and wait. If nothing happens try playing with it until it exlodes. XD


No need to buy. KO2 is what should be forming spontaneously as K reacts with air.

EliasExperiments - 22-3-2021 at 09:48

Well if you want to wait for KO2 to form on it's own you would have to wait month or probably even years. I don't know if there is a way to accelerate it, by storing it under pure oxygen.
I mean KO2 is somewhat expensive, but certainly affordable enough in small amounts to test that. So probably wound't be worth the effort.
If you just put NaK in air the moisture and CO2 in the air will destroy the KO2 again. You can only let it slowly react under mineral oil.