Thunderf00t - 2013-01-30
I think I've finally come up with a reasonable explanation as to why alkali metals explode. In the rare event of a good contact between the metal and the water (usually hydrogen generated on the interface keeps the reagents separate), the electron transfer happens rapidly, leading to this situation: Na+ Na+ Na+ Na+ Na+ OH- OH- OH- OH- OH- H H H H H Now the sodium and the hydroxide being next to each other isnt a problem as they attract, but having the cations next to the cations, and the negatively charged hydroxides next to each other will create a force moving these ions apart. This will cause new sodium atoms and water molecules to come to the surface. This is the sort of positive feedback mechanism that you need in order to get and explosion. Now I have to tip my hat here periodicvideos here as it was their new footage that got me thinking about this problem again. Sure I had loads of high speed studies of this, but had ultimately come to the conclusions that whatever was happening was beyond the capability of my camera. However the periodicvideos camera looks to run at ~1000 frames per second, and they are still probably an order of magnitude outside of the regime they need to be looking at. Sodium is also a poor choice as it tends to explode less, and just stably fizz on the surface. Probably the best target for getting the required results is 300mg (1/3g) of potassium in a good quality wine glass filmed from underneath. Potassium almost always explodes in relatively short order, and I never got these sorts of quantities to destroy the glass. There are also a LOAD of other smaller things that make me grind my teeth in these videos as you really dont have to think long or hard to work out that these are either urban myths or bullshit. Like saying the guy in the middle of the explosion is more likely to survive because the explosion goes out from where he is. If he is in the middle of the explosion, the gas will have permeated his clothes. Any exposed skin will suffer burns from the ~2000 degree fireball. Further the pressure wave will also mess you up pretty badly. Its far more likely that someone sets off the explosion will actually set off a limited burn, that can lead to a explosion elsewhere. Let me put it another way, these is all demonstrated by the example of a hydrogen oxygen explosion. They guy standing a few meters away very sensibly has ear protectors on. Had he been in the middle of that when he set it off it would have messed him up royally! At the simplest level he would be stood in the middle of a 3000 degree fireball!
Just seen you all over the science news pages. Theory proved! Well done TF :)
alexanderscottduff - thunderfoot deserves very much more respect than he gets, thats for sure.
Sometimes when Thunderf00t just talks science, I want to bearhug him.
My brain hurts, in a good way.
Try Gavin Free and Dan Gruchy from the Slow-Mo guys, maybe they'd help out with that lol
Or ratedrr. He can do 10000000fps (ten million).
So, 18 months on, did you get a response from @Periodic Videos ? Have you been able to test your hypothesis further?
I wonder if this can explain the explosion of thermite on ice
It's pretty disappointing to see that Periodic Videos ended up being a little lax in their fact checking.
Congratulations, Thunderf00t! Keep experimenting! I know you will, but don't stop! Like you said, scrutiny makes science stronger! Thanks for the videos you post! I wish I knew you or even someone like you in person who takes science seriously. Unfortunately, that seems to be a rarity where I live.
i agree! there hasn't been a good explanation for thermite and ice!
I recommend this TED talk: "Ramesh Raskar: Imaging at a trillion frames per second" Obviously very improbable he could get his hands on that.
4:11 GLaDOS moment!
4:03 where the information about colour of sodium gas comes from? I will be grateful for it.
BTW. Why it is that hard to find info. about things like this? I mean in new books, and even in internet nobody get these facts together.
@Thunderf00t While using an Oxy-Acetylene torch yesterday cut some steel beams I had an idea which might apply to this situation as well as a method to test my hypothesis.
As everyone knows steel oxidizes in air to form rust, this reaction however is very slow...if you put only steel and oxygen together in a sealed chamber you will have a very long wait to get any appreciable Fe2O3..There are, however, at least a few ways to speed this reaction up. One way is to heat it up and hit it with concentrated oxygen like I was doing with my torch (An oxy-acetylene torch doesn't actually get hot enough to melt steel, it heats the metal up and then hits it with a concentrated jet of oxygen resulting in VERY rapid oxidation of the metal and the resultant jet of plasma is what cuts the steel).
Another way is to get it wet...if you put a few drops of water on a nice clean unoiled piece of mild steel you can literally see the reaction occur, you can watch it rust!
The speed of the reaction is at least thousands of times faster than Iron and oxygen alone and I believe that is the cause of the sodium exploding when it is placed in water.
Maybe the chemical equation is something like this:
4Na(s) +2H2O(l) +O2(g)= 4Na1+(aq)+4OH-1(aq)....Na1+(aq) + OH-1(aq)=NaOH(aq) And yadda yadda yadda there is no free hydrogen being produced to form a barrier between the reagents yet. Anyway the reaction is not hampered by the need to break the ionic bonds between hydrogen and oxygen because the OH radicals are already there so it can occur very rapidly and release much more energy than the simple re-oxidation of hydrogen...
Experimental tests of Hypothesis:
1) BORING!!! Put the water in a vacuum to remove all dissolved gases and then do the test in a 100% nitrogen atmosphere to see if the explosion still occurs. If my hypothesis is correct you will get no explosion.
2) Potentially NOT BORING!!! Place your (ice cold) water container in a 100% Oxygen atmosphere at 100 ATM until equilibrium is reached then repeat your drop test of the sodium. You will have at least 500 times as much dissolved oxygen in your water sample plus a little bit more if you use cold water...
Please be careful if using method 2 and by all means post a video!!
Preform a burning split test after adding Na to water and you'll hear a popping sound. Therefore H2 gas is produced.
Great vid and I would love to see that reaction in 10000 fps. I.m courious if you're right :)
That amazing moment when one of your favorite Youtubers *Tf00t* makes a video response to another of your favorite Youtubers *Brady Haran* !!!
Neat video. I always assumed the explosion was caused by the reaction reaching the autoignition temperature of hydrogen.
Damn, i can feel my brain expanding when i see thunderfoot videos ^^. Peace man!
Talk to the Slow-Mo guys about fast cameras.
I'm not a stalker I just watch rooster teeth and their podcast. Being literate and being smart is two different things I did the research before hand. Pointing out my illiterate instead of doing the research before hand just show that one of us is smart and one of us is literate.
+Cam Tolley LOL, I suppose it does!
sorry if I was a bit harsh I was quite tired when I made the comments(i woke up two hours earlier than usual) hope I didn't cause any hurt feelings. I could take those comments down if you like.
+Cam Tolley Nah, it's cool bro. discussions fuel creativity and innovation. For instance, I had no idea the Slow No guys only get together once in a while to make their videos.
If you watch their videos in bulk you will notice that gav's hairstyle won't change for half a year or so and then the next week it will be completely different.
Is the energy released in the "Coulombic explosion" equivalent to the lattice enthalpy of NaOH?
I'd really love to see this done by Destin on SmarterEveryDay!
I'm eagerly awaiting the moment when I take college chemistry and this comes up.
More than just the science of these types of explosions which was absolutely fascinating, I found the most interesting aspect of your observations to be the social phenomena. There seems to be a deep seated psychological tenancy to not challenge the accepted theory despite is obvious inconsistencies. The fact that irrational and flawed explanations of such common phenomena are being overlooked by credentialed educators represents a disturbing tendency of the social system to reward conformity and punish dissension. It is also interesting that it took a dropout to see the inconsistencies that graduates became blind to through the process of being educated.
Nerdfight! Great work tfoot! Love it when you talk science. So are you hoping to get this named as the "Thunderf00t Effect?
ooooh yeah i remember that. i cant wait to see how this hypothesis pans out.
Brilliant, one of the best Tf00t vids in my view.
This is brilliant! :D I do hope we get to see a ten thousand frames per second recording of it and see this effect and test Tf00t's hypothesis.
LOVE this kind of stuff!!!
So, when is your Nobel prize nomination?
Also, when will the first Coulomb bomb be produced?
Thank you for proving my point.
great i love your logic man, really good work and good thinking. i was thinking something like this in my mind in slowmo but your explanation and logic is way greater than mine :)
@Thunderf00t get the slomoguys on it with you!!!
This is awesome. Thanks so much for sharing!
Mmm, this can be interesting when periodicviodeos reply... just wait a moment: I'm going to make some pop corn first!
I'm so proud of you, Thunderf00t! You are awesome! I love watching your videos! I can watch them, again and again, and this one in particular is amazing! Congratulations on this discovery! I wonder why Periodic Videos won't take you serious? Maybe they're embarrassed, or maybe it's because of the controversial issues you make videos about. I like them, but ignoring your discovery makes them close-minded.
With regards to getting higher FPS recording, maybe try to get in touch with The Slow Mo Guys? They have experience with high speed video, and they have the technology to do it.
"behold, I am become death, destroyer of wine glasses."
The Thunderfoot reaction?
Well, I'm convinced of the hypothesis. But now I want MORE DATA!
See, this is why I still watch this channel. This kind of thing is awesome to know about. ^_^
Wow i hope they take it as a motivation to clear it :D
Keep up the great work tf00t!
I'll just wait for wazooloo to make a video on this - that should settle it ;)
Interesting video, Hope you manage to get the work done to continue this! it's be cool to read about any studies you have
You know, Thunderfoot, I have always wondered the same damn thing. I remember wondering it when my brother first told me about a teacher that threw some sodium in a puddle. "how can there be an explosion? wouldn't it be just an incendiary?" Thank you, God bless your intellect and beginners mind.
I'm glad you're back to maknig videos like these. You had such a long time where you were too political, imo.
Hmm, very interesting and cool. And a comprehensive explanation.
Seeing that propane explosion reminds me of the train derailment in Mississauga, Ontario, Canada, (in 1979) which lead to the evacuation of the entire city. There was chlorine being hauled by the train as well as propane gas and that's why the city had to be evacuated..
thunderfoot, I would like to ask u a question. I love chemistry and want to be a chem engineer, and I would like to know why exactly it is reactive, you go over it in your video but it went over my head a bit. could you please explain what exactly happens and why.
thunderfoot you may want to contact 'the slow mo guys' for this, they have a camera that can operate at tens of thousands of frames per second.
its not as much of a science channel as it is a 'ooh look its pretty' but you might get them to agree
@Blox117 hmm looks like your first comment was removed as spam.. its back now.
@Blox117 @SonarWavePulse i have seen this before and have forgotten about this technique. i thought you were talking about something completely different. simple misunderstanding :)
@1wsx10 okay, but why was my comment removed as spam? :p
@Blox117 i dont know exactly how YT spam prevention works but probably because it was 2 words and a link
+1wsx10 +blox117 The camera Blox is talking about isn't an actual slow motion camera. It uses the stroboscopic effect to simulate slow motion. Each frame is actually a different pulse of light.
@ronettreker i never said it was a "slow motion camera". well i suppose you didnt say i said it either, nevermind.
NolanSyKinsley - 2015-11-28
Sounds like a job for Slow-Mo Guys and their fancy kit.