Everyone’s seen the Diet Coke and Mentos “experiment” that ends in a brown eruption. But have you seen the Coke and Propane experiment insanity that results in a rocket launch? As [Itay] pointed out when he sent us the tip, this doesn’t need to be lit. The simple act of turning the bottle upside down starts a powerful reaction without any ignition.
Of course it’s the how of this that tickles our brains, but let’s finish the setup. This starts with a bottle of Coke which is about 3/4 full. The head space is displaced by spraying propane into the bottle; propane is heavier than air. All that’s left is to turn the bottle upside down and pray it doesn’t smack anyone in the noggin as it takes off.
In trying to find an explanation for this phenomenon we came across a plausible answer on the Chemistry StackExchange. It points to the Mentos phenomenon combined with the temperature differential caused by the very cold propane. The answering user theorizes that tiny ice crystals form and when the bottle is turned upside down the cold propane and micro crystals rise through the warmer soda acting as a much more rapid catalyst than Mentos alone. Of course this is just a theory so please share your own ideas below.
We thought the folks who microwave stuff outside of a microwave enclosure had their fill of danger but this videos is also one of theirs. It should be no surprise that they also tried the experiment with an ignition source. That video is found after the break and should immediately convince you to never try any of this yourself.
LOVE IT.
Russians are nuts just getting in that cold water.. No wonder they like the cosy appeal of fuel/air explosions.
They are not russians, they are ukrainians and they left thru Ukraine-Russia war at Lugansk and Donetsk regions
Don’t confuse us with your so-called facts! They’re north of China and East of Germany. That makes them Russians!
:-)
if you ask a stranger what you see at 1:57 they would probably say :”the wiew inside a nuke exploding.
I am no chemist, but a simple guess would be :
Each basic Carbon atom has four binding points. Each carbonated beverage contains CO2. Propane is a carbon heavy fluid.
So, it could be that the double carbon bond that develops upon mixing(between carbon in drink and carbon in propane), frees 2 parts oxygen , which are then free to reconnect at another point in the carbon chain. Which ultimately releases a group of unstable hydrocarbons. Which is why the end result is still flamable.
That… doesn’t really make a great deal of sense. CO2 is already fairly stable – it’s a combustion product, not a fuel. The energy required to liberate oxygen from CO2 is equal to or less than what you get from burning it again.
Was waiting for this response. Like I said in my disclaimer, not a chemist, was just a severely under-educated guess. Didn’t account for the fact that both oxygens are double bonded to a single carbon, I thought these were on single linkages, leaving two open nodes per carbon.
Usually when people say they’re not a chemist they mean they didn’t study it at university, not that they have never studied it at all. Why even comment with this made-up gibberish?
The gas boils around – 40 but tge liedenfrost effect here stops it being boiled by the soda instantly. When the bottle is turned upside-down the gas mixes with the soda and instantly boils forming gas, as the gas has a much larger area it forces the soda out of the bottle causing it to take off.
That doesn’t look safe at all.
:-)
By turning his face away from the exploding bottle, he increases the width of his head, increasing the chance of a random trajectory hitting it. if(when) the bottom of the bottle bursts, there will be one or more direction changes, so the second time it aims for your head, it may be from a random starting point :-)
Alright, who’s got the Zapruder film for this one? Was there a second coke bottle on the grassy knoll?
Yes, but these plastic fragments are unlikely to be life threatening to your skull, whereas a frag of plastic to the eye: good bye eyeball.
From the insane guy that use-his-microwave-canon-on-a-stick, this experiment looks safe.
What is happening with HaD… Really, c’mon, seriously guys? This is definitely everything but safe. Are you sure that this is the kind of content you want to be posting about?
Pretty sure they called it “insanity” and asserted that you should “… never try any of this yourself”…
Regardless, it is still taking a conventional item and using it in an unconventional way; i.e. A hack. So, its a fair ball.
You’re looking for http://www.Nanny-a-day.com.
Hey, this isn’t a real site! This guys a phony! A big fat phony!
Are you dumb enough to do anything you see on the internet ? Do you think we are ? And when, should it not be our own decision ?
Maybe not safe but loads of fun!
Wow, that is such a stupid thing to do. I’d love to see it done. :D
I think the explanation is simpler: as liquid propane is less dense than coke, which makes it float on top of the bottle setup. As soon as you turn it upside down, it gets confined. But as you can see in the video, it readily boils at room temperature (boiling point: -42ºC). As a result, the coke gets expelled from the bottle opening, much like combustion gasses are expelled from an ordinary rocket, and by conservation of total momentum, the bottle is launched in the opposite direction.
My gess is it should work as well with plain water instead of coke.
This. I saw this a while ago and was the conclusion I came too.
If you look carefully, it’s actually liquid propane sat on the surface of the coke – not a gas. When inverted it boils rapidly taking heat from the coke and becoming confined in the top of the bottle. Thrust is produced as the coke is propelled out the nozzle.
I’m not sure if the CO2 in the coke has an effect or not. Experiments might be necessary…
Look carefully at 0:35. Best on full screen and full HD. You can clearly see ice on the surface of the coke and a liquid above it – the propane/butane.
That’s a coke icee, covered in a thin layer of soda. It should appear as a yellowish liquid.
Recanted. It very well could be propane.
How could the propane still be a liquid at room temperature without some phenomenal increase in pressure that would have torn the bottle asunder before the experiment began?
To answer myself:
OBVIOUSLY, the vicinity around the expanding gas cools, as the injected liquid propane absorbs heat. Which ultimately cools the soda to a point <40C, which results in a comfortable platform upon which liquid propane may float without boiling off.
(Hates feeling Stoopid)(Loves Learning)
It’s really cold. Not sure if it’s propane or butane, but I’ll use propane in my description. It might even be a mix.
When it leaves the propane canister a certain quantity of the propane will expand a huge amount. That is accompanied with a drop in pressure. Some of the propane will remain liquid with the temperature drop. This is pretty typical of what happens when emptying one of these bottles – if you’ve got one, or even something that uses propane as a propellant, invert it and squirt a load on a surface. You’ll see it collect as a liquid and boil off as it warms up.
As the propane has squirted into the bottle of coke a layer of ice has formed. Liquid propane has collected on top of the ice. It won’t stay liquid for long – it’ll boil off as heat is transferred into it from the surroundings.
However, when inverted the liquid propane is mixed with the warm(er) coke leading to rapid boiling of the propane. The resulting gas is confined in the bottle and forces the liquid coke out of the nozzle.
At least that’s my take on it….
Ah, I mean drop in temperature. The expansion from exiting the bottle is accompanied by a drop in temperature, not pressure.
That lunchtime pint is catching up with me…
Sounds good to me.
As you have pointed out, the propane boils off/(sublimates?) at room temperature, so the bulk of its expansion occurs long before the bottle is tipped over. This should result in minimal pressure.
Good news is, I have plenty of coke bottles, water, and stupid neighbors. Will pickup can of propane and get back to you later. j/k
Hi donkesystripes! As you point out, the propane does boil at room temperature, but the liquid propane that collects after a while of filling the bottle with the decompressing propane gets cold enough as to stay in the liquid form. Then, by inverting the bottle you force a huge heat transfer from the water to the propane, and you get a lot of gas production/pressure from the boiling, as mechanicalsquid described.
Even the liquid spherules that are ejected from the nozzle are subject to the same laws(i.e. They will evaporate at room temperature)….
Ah hah! Unless the soda is cooled to a point <-40C, where it can liquefy!
See, that would have been so much easier to say.
Yeah! In fact, the upper layer of the coke gets below – 40ºC, and becomes ice, which helps further insulate the liquid propane from the bulk of the coke. And fortunately, it floats in between both liquids! You always have to remember that this kind of systems is not at equilibrium. So there’s a lot of temperature gradients going on, and it’s not easy to describe.
I blame the Mathematics of wonton burrito meals. Damn you Professor Farnsworth!
It sure works for plain water instead of coke. Just use the search terms water butane rocket for video.
Hm… anyone want to repeat this with LN2 and water? or LCO2 and water? No fire danger, less mess, and potentially just as impressive :D (oh and fins, fins and a nose cone would make the insanity more predictable)
I wonder if maybe it’s even simpler- liquid propane sitting on the inside surface of the bottle neck, which having low heat capacity will easily cool to below the gas boiling point, until the coke hits it when the bottle is inverted.
LN2 would be great, lot of liquid expands rapidly to gaz at room temperature.
Unfortunately, LCO2 doesn’t exist in our living world standard pressure: only gaz or solid.
CO2 sublimate (solid to gaz) directly at standard pressure. Check triple point rules. You can obtain LCO2 under 5 atm and more…
https://en.wikipedia.org/wiki/Triple_point
Savety doesn’t seem like their number one priority :(
It would take like 15 minutes to build a safe, remote operated launcher for this. Some wood, a hinge, a rope. That’s all it takes.
That doesn’t sound Russian to me.
Except they are from Luhansk, which is still considered to be in Ukraine, not Russia :P
American safety, Russian safety, ALL MADE IN TAIWAN.
Sometimes you just gotta throw CtAhUeTwIiOnNd.
They are from Ukraine
Yes, but the implied quote was from a movie.
This is a standard butane bottle. Butane has a higher boiling point than propane. (-1 vs -42 C) you would not be able to do this with propane.
amazing how far I had to go down the page to find this. Butane, the bastard gas, not propane nor propane accessories. Might be iso-butane. The walls of the fuel can are not thick enough for propane.
It’s not hard to see from this video why Russian men have such a low life expectancy, only 65.3 years according to Wikipedia:
https://en.wikipedia.org/wiki/Demographics_of_Russia
Vodka? Karl Marx’s idiotic ideas? Stalin’s terrors? Probably all them and more.
Good, good. Let the hate flow through you:
http://cdn.meme.am/instances/62288458.jpg
Oh, btw, they are not russians…
Didn’t you watch The Young Doctors Notebook? The reduced life expectancy is because of syphilis(and the drops).
Karl Marks was German who wrote what he is most known for i.e. “Capital”, what I presume you care to consider “idiotic ideas”, while being in England.
Read Karl Popper’s “poverty of historicism” and the related books to see why the ideas were idiotic. They’re based on a philosophy that borders mysticism, and much of Marx’s work is just applied bullshit (Dialectical materialism).
Marx had a few good insights about economics and society, but most of it was pseudoscientific dross.
Holy moly is that still shot on the youtube link showing a hole in the smoke where the bottle passed through maximum dynamic pressure (or something) on it’s way out? Couldn’t be passing mach…could it?
That thing sure accelerated fast so it seems plausible, at least to me.
Wow.
Negative. Negative. It just impacted on the surface…
I MEAN it was just the propellant running out at that point.
Still awesome though.
Got to love those eastern European guys ;)
How can you discover this and not do some basic experimentation to determine things such as whether or not the carbonation of the cola is relevant?
Second video made me mad. Good way to start a forest fire @#$%&@#$s. I suppose that picnic table belongs to them too, and they swam out and collected all those bottles when they where done wit them? Way to promote banality hackaday.
Have you ever ignited propane? It burns off almost immediately, transferring very little heat to the surface. Note how they’re not screaming and holding horribly burned hands and arms, either.
Not to say what they’re doing wasn’t extremely dumb, but it’s not likely to have damaged the table or started any forest fires.
Considering where they are and what is happening around them (google “Luhansk”), I don’t think anyone would care that much…
I don’t think that word means what you think it means…
I don’t think the SE answer mentioned in the article covers enough. donkeystripes and nevermore78 have it about right, and there is another answer on the chemistry.SE now that includes the result with and without the added effect of releasing co2 with your butane. http://chemistry.stackexchange.com/a/39252/15065
Don’t forget that MechanicalSquid was whooping on my ignorance too!
Now I’ve been busted for being a lazy speed reader! Really the important question is: who is going to try mixing liquid-O2 and liquid butane for a REALLY fun one? That’s where you get the multiplying effect of 2C4H10 + 9O2 -> 8CO2 + 10H2O, for almost twice as much expansion, plus MOAR FIRE
don’t do that
Ouch, my insurance!
2C4H10 + 9O2 -> 8CO2 + 10H2O
Are you sure about this?
2C4 =8C
2H10=20H
9O2=18O
Where’d the extra 8 O come from on the right hand side?
My 13s look like 9s, always have ;)
I remember my chemistry teacher talking about how he mixed acetylene and hydrogen peroxide once when he was young to build a torch because he was unsatisfied with the flame he got from burning acetylene in air. I don’t think he told us how long his hand needed to heal…
I love these guys…
This would have been my friends and I if we were born 10-15 years later! Instead all our hijinks both went unrecorded and relied only on our own ingenuity, as the internet was not available like it is now.
kreosan is amazing. check their youtube channel for more extreme experiments. my favourite is the welding one with salt, water, and two razor blades. although i don’t understand a single word they say, it’s a load of fun.
not to mention their home made wifi antennas.
https://www.youtube.com/user/kreosan/videos
Shouldn’t people post their hypotheses and not their theories? At least not until the process is understood and proven? Just sayin’. I know it’s pedantic but maybe people in the scientifically literate crowd should be using the right lingo.
Bureaucrat #33, you are the best kind of right. Touché.
It’s said to work much better with liquid nitrogen:
https://www.youtube.com/watch?v=vAt8dSV_tJk
and in slomo:
https://www.youtube.com/watch?v=qiN0qmHtwKo
(videos are from a really neat german-language podcast, http://minkorrekt.de )
Looking at other videos on their English channel, I’m seeing a lot of rapid experiential learning in a bombed-out Ukrainian city with an the absences of available education, electricity, money or laws. These guys might prefer death at their own hands rather than randomly getting blown up by any of the many unexploded missiles around, but what they’re learning might save their community also….. It all looks pretty desperate.
They actually live in a reasonably big city in what used to be (and de jure still is) the most industrialised part of the Ukraine, and the war has been going on for just about two years, so education/educated people aren’t really a scarce resource; this isn’t Somalia. One of these guys actually used to repair electronics for a living. Besides, they started blowing stuff up long before the hostilities began. So my guess is they are doing it for fun, not out of desperation.
You are flash boiling the butane which rapidly expands into a gas thereby expelling the liquid from the bottle
You can use a can of electronic duster too. Just invert the duster and spray liquid (R134a) into the coke bottle and you’ll get the same effect.
Sorry this is a double post I tried commenting before logging in and the comment didn’t show up for about 10 minutes so I posted it under my account below.
You can use a can of electronic duster (R134a), Turn the can upside down to spray liquid into the top of the coke bottle.
He used Butane first and then Propane. OR are “tourist burners” also Butane? And why do they burn tourists?
I think that there could be more than boiling going on there. There could be a phenomenon known as Rapid Phase Transition (RPT) that is well known to the Liquid Natural Gas (LNG) industry. It is basicly rapid boiling that strips away the boundary layer and makes heat transfer go through the roof. It happens so rapid, that it can produce the same results as an explosion. This is of particular interest in the LNG industry where they are piping cryogenic liquid onto ships and a leak could have really bad results.
Here is a great vid of RPT in action. Again, the explosions seen in this film are purely due to a phase change. there is not any detonation/deflagration going on here.
https://www.youtube.com/watch?v=h-EY82cVKuA
https://en.wikipedia.org/wiki/Rapid_phase_transition
I used to work in a “funnel cake” stand at an amusement park managing 15 year olds. At least once a week a kid would throw an ice cube in the fryer. Water being denser than oil, the ice cube sinks to the bottom, melts, and heats up to the boiling point over the course of a minute or so. All at once the water vaporizes into steam, erupting hot oil everywhere. Quite dangerous, but that’s 15 year olds for you!
Here coke is the oil, butane is the ice/water, and the fryer just happens to be shaped like a rocket. Flipping it upside down spurs the rapid phase change.