I know that you're talking about people looking like grumpy cat in this post but I have the explanation for it exploding. You all know how sometimes ice will crack when you put it in water, well the explosion is that on a more extreme, large scale. Heat + ice = cracked or melted ice, depending if it was slowly exposed (melting) or if it was instantly introduced to the heat (cracked). If it was instantly introduced to the heat it wouldn't have time to react (melt) so it would crack. In this case it would be exposed to extreme heat almost instantly leaving no time for it to melt or give off steam and since it isn't just a little warmer like water it would crack and trying to distribute the heat but in this case there is too much for it to distribute and not enough time so it would just explode into a bunch of little pieces. To prove this just look at the ice left over, does it look melted or torn? And the truth is that is was torn not melted otherwise it would be smooth.
This is hardly a mystery. Any foundry or steel mill worker will tell you that molten iron (like one gets from Thermite) will often incapsulate moist, water and ice on contact, resulting in a gas explosion.
I thought that too but I’ve seen videos where thermite is dropped directly into water and it doesn’t explode. The slo Mo guys did a video on it I think.
I think I like it better when they confirm internet videos then bust them. By default I am expecting an internet video to be a fake so it is nice to see a real one.
Actually it's not just a speculation that thermite decomposes water to oxygen and hydrogen. It does. That's why steel works have safety rules against bringing anything wet (including water) near the furnaces or molten steel.
@@halsosabowski2400 Yeah im guessing once the molten iron cools down enough the molten metal contacts the ice and creates a ton of steam at once and BOOM.
I was taught the thing about hydrogen aswell when working at a steel plant. They left the gates open in the winter due to the explosions being very frequent when there was snow on the recycled steel from outside. We also used electrodes to melt the steel and that might have something to do with it aswell.
@@halsosabowski2400 I agree with you on the flash boiling hypothesis. I think the reaction melts the top block of ice, and when the molten metal drops into the water it causes the water to flash boil.
I think they are forgetting the very definition of an explosion: rapid expansion of gases. You are vaporizing 0C water at 2500C in an instant, what do you expect to happen?
really really hot water vapour result in the destruction of the water molecula in dihydrogen and oxygen then fire + dihydrogen + oxygen = boom ...... didn't you know guys ?
quelorepario dry ice is not water so there is no hydrogen in C02. However there is fuel=Carbon, Oxygen and heat=thermite so it could exploded based on those three components. The thermite through an exothermic reaction could separate the Carbon and Oxygen. This is cool.
Best explanation I got: That termite is burning at around 2500C, which is 25 times waters boiling point. What happens is that the second that the bucket gives way to the thermite, the ice transitions directly into steam (vaporization). Vaporization is a very energetic process, so it makes sense that it would create a blast the way it did.
@@blackmagicprod7039 The boiling point of water is 100 degree C by definition (that's who the Celsius scale is defined: 100 water boils, 0 water freezes). 2500 is 25 times 100.
Steam explosions act just as you say, but some metals can either chemically react with the H and O or cause High-temperature electrolysis. The stated temp for HTE and the burning temp of thermite are both given to be ~2500C. If HTE occurs, then what Jamie describes at 3:17 is exactly what is happening (after the initial steam explosion).
I think it's a mixture of the water vapor, and jamie's aerolisation theory. The thermite is a powder that's on top, burning downward. When the water melts and turns to steam, it will go the path of least resistance, namely straight up and through the powder. This will carry lots of thermite powder up, which then all ignites together. Probably something like a dust/flour explosion.
Considering expert scientists aren’t quite sure how the thing they’re doing is happening, I think we can forgive him for being a little ignorant on this one.
Corey I’m talking about 3:11, where the narrator and Jamie say the experts they talked to weren’t quite sure how the reaction was happening. I am currently at Uni for my Bachelors in Physics. Scientists constantly work on problems and experiments where they aren’t sure of the outcome or reasons behind an effect. Everything that is understood becomes a thing to study while scientists’ real focus is in the unexplained. If we understood how everything worked, there would be no need for scientists, but just people who knew things.
Corey “Experts” is open to interpretation and I would hope they were talking to professors in thermodynamics (maybe what you mean by explosives experts), but I don’t think they were consulting bomb technicians. I think I’m using the word “know” differently to how you do. I don’t know what your background is, but the language I hear about experimentation is “suspicion of an outcome” or “reasonable model for application to a scenario”. To know something means the experiment has already been done multiple times with peer review. The scientists I work with are the first to say they don’t “know” if an experiment will go the way the theory stated. To do so would be sort of arrogant. And experiments involving unknown conclusions have about a 2/3rds chance of going with the expected outcome.
Wait a minute. This is a thermite reaction. We have a buttload of oxidation going on, and a temperature high enough to split water, so not only will we expect a Hydrogen explosion, but the extra Oxygen present would drive the thermite reaction into a rapid oxidation of both metals as well, increasing the temperature. There's your positive feedback loop.
For that to happen, the H & O2 need to be in close contact and in the right concentration. Unfortunately, there's no containment vessel preventing the H & O2 from dissipating.
You are essentially describing an endothermic and an exothermic process with the same energy somehow releasing a boatload of energy. They would just cancel each other out. Water decomposes, decomposed elements turn into water again. Somehow explodes. How does that make sense? You are putting in energy to decompose the water, then you are releasing that same energy when the water recombines. This sort of thing can lead to an explosion when there is a long enough delay where the gas mixture simply accumulates before going up all at once but that simply isn't what we saw here.
The camera work and editing on this video is a work of art. They perfectly get the explosion, the reaction, and showed every angle when it needed to be shown.
Speaking from my experience with hydrogen dissociation in retort tube furnaces, it's more than possible. The furnaces I work with only get up to about 2000 degrees Fahrenheit, but they dissociate a little less than a pint of water per minute, which translates to around 1000 cfm of hydrogen and oxygen. If our burnoff stacks go out, catastrophic levels can build up in seconds.
A good control test would have been to substitute dry ice for ice. You would still have the vaporization and volume increase but you eliminate the possibility of H2O-> H2 and O2 -> to H2O.
I suspect what happened is that the heat of the thermite caused the water inside the ice to boil fast enough to a high enough heat as to make the resulting high-pressure steam blow apart the ice blocks.
Seems the most likely explanation, plus once the high pressure steam blows the thermite into a "cloud" that would burn rapidly too making the explosion even bigger.
Terence Person No, they said that the thermite somehow turned the water into hydrogen and oxygen, which then rebonded and exploded. I'm saying that it's high-pressure steam.
it seems a lot of people in the comments thinks that it's steam related but I think Jamie's reasoning (although not intended towards steam) holds true. To get a steam explosion you must build pressure then quickly release it, there is no way for pressure to build in an open system like this so it seems very unlikely to be a steam explosion. The best explanation I can come up with for why it could be a steam explosion is that the thermite quickly burrows a channel into an ice block where it sublimates a spherical cavity. meanwhile, the molten iron/aluminum/steel bucket/water have plugged the entrance to the cavity allowing it to begin holding pressure, resulting in a steam explosion. I have no clue if that's true though
ok i was curious so I googled it and someone did their masters thesis on it! Look for The phenomenon of exploding ice - conditions and explanations by Valmadre, Dominic (2016). Here's a portion of the abstract of the essay: "It was found that the explosion in question was most comparable to a boiling liquid expanding vapour explosion. The thermite reaches a molten state and penetrates through the bucket in which it was stored. Then, it flows into the core of the ice block where it creates a pseudo short-term pressure vessel. The standard thermite redox reaction continues to occur within the icy chamber causing a localised increase of pressure and a liquid-vapour equilibrium to arise. After a few seconds, the icy shell ruptures, resulting in a rapid loss of the localised pressure as it reduces to the atmospheric pressure. A small splutter will occur at this stage as water vapour and droplets are expelled from the system. After the system equalises, a volume of superheated water will exist that will then violently evaporate from 0.0144 m3 of water to 19.6160 m3 of water vapour. The remaining ice shell shatters in a brittle manner and the rapid gas expansion is the driving force of the observed explosion. In chapter 5, illustrations of this process exist in a set of steps that clearly demonstrate the phenomenon. The findings of this project were significant as it was discovered that, with the exception of the exothermic thermite redox, the explosion was driven by purely physical means and without chemical reaction. "
@@mantissa182 you can get a steam explosion in open air, you just need enough heat flash vaporizing ice into steam. It's like how if a even a couple drops of water gets in an open foundry it will cause a steam explosion that will send molten metal all over.
There should be a fairly easy way to test the two theories offered by Jamie at the end of the video for why the explosion occurred. Assuming that it is one of the two, then you could try the experiment with varying amounts of ice and thermite. If increasing masses of ice produces a higher yield explosion, then it is likely that the 2H2 + O2 being ignited is responsible for the explosion. If increasing masses of thermite produces a higher yield explosion, then it is likely that eitehr the thermite is being aerosolized or that the ice is in some way influencing the thermite as opposed to the thermite influencing the ice.
I'm surprised that they did not suggest that once the thermite melted through the base of the bucket and was completely encased in ice, it quickly vaporised a large amount of water (Because thermite is 3 times hotter than volcanic magma) which would then carry any remaining powdered thermite, as well as much of the molten thermite into the air. This can happen because the melting ice would create a water barrier that would not allow the gasses to escape fast enough out the sides so it would attempt to go up, unfortunately that would be blocked by 10 lbs of molten thermite and so once the core of the block (which is now boiling water) flash boils, the massive expansion of gasses would push everything out very violently
Would not the ice turn instantly to gas at those temperatures? And is not it this gas sealed by the molted iron/higher temperature of reaction of the bucket which is above it?
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Bart Hoving The water doesn't go instantly from below freezing to above boiling. It takes time to transfer the heat energy, so the ice needs to melt before it can boil.
Mikkel Højbak the point is that at those extreme temperatures the transition is so fast there is no time to build up fluid. In all practicality it is instantly turned into gas. Damn termite melt through iron almost instantly like it is butter, and iron melts at 2000 degrees Celsius and can hold more heat energy than water. I'm sure the termite has no problem at getting the ice up to 100 degrees Celsius almost instantly, in fact I'd be surprised if it didn't.
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Sure, there is no buildup, since the water boils just as fast as the ice melts. That doesn't mean that it skips the liquid phase (sublimation), though. There is just very little liquid at any one point in time. My thoughts on the reason for the explosion: The very first thermite to hit the ice block will most likely be cooled down enough to transition back to the solid state, effectively encapsulating the ice in a thin layer of solid metal. The now very hot, confined steam inside will then eventually burst the surrounding ice through the buildup in pressure.
Mikkel Højbak I think it is just the opposite, I think that the water that is trying to escape out the sides and top freeze in the cracks between the blocks to create that seal. then maybe something similar to what you said blocks off the top. but this whole thing is incredibly complex, so it is tough to say for sure... next time they should put a gopro inside the ice to watch and see what happens.
You know how ice cracks when you put it in your drink? I remember watching a documentary on the building of ice hotels, and how they had to make sure the ice did not heat up as they worked with it. The ice could crack and "explode" (as they put it) because of how compressed ice blocks are. Perhaps the same thing is happening here. The ice blocks are heating so quickly that they explode into chunks of ice. That would explain the force, but not the glowing particulates.
From wikipedia: "High speed camera imaging of alkali metals exploding in water has suggested the explosion is a coulomb explosion.[3][4]". www.nature.com/nchem/journal/v7/n3/full/nchem.2161.html Not sure I'm convinced aluminum has that same behavior. Now, we know aluminum does react with water, typically "slowly", producing hydrogen. Maybe the huge surface area of the aluminum dust coupled with (almost pure) water vapour helps the reaction happen quickly. I think this is very interesting because it seems that maybe there's more than one factor contributing to the "explosion". But maybe it's really just steam and nothing else.
Either way, to check out if the water contributes much to the reactivity of the whole thing, you could do the same experiment using dry ice. The molar volume change of dry ice is very similar to (water) ice, so the expanding gas/steam factor should be about the same.
What's so hard to understand. Thermite gets extremely hot very quickly once ignited. The gas simply can't escape fast enough from the ice; therefore, boom. It's no different if you throw a frozen steak on a hot pan with vegetable oil inside it. It pops.
Either method seems limited by the fact that there would be no accumulation and thus no sudden boom. There is no container keeping hydrogen and oxygen contained, and there is constantly enough of an ignition source from the very beginning of the possibility of water splitting. So if it was this method, they would "explode" just as fast as they were being separated, making a strong steady burn instead of an explosion. The aerosolization method seems more plausible, if the conversion of ice into steam is that dramatic. However, the explosion seems to have originated at the base, right at or within the ice. There doesn't seem to be enough room for all that thermite to be aerosolized like that directly under the bucket. More importantly, if you look at the infrared vision, you'll see that some thermite had already made it down to touch the ice on the side, exposed to air, and there was no explosion there. There was plenty of clouds of fire spraying off the side, which could well be due to aerosolization, but it was not nearly violent enough to create this kind of shock wave explosion. My guess is that this is very similar to their microwaved jawbreaker experiment, and that this explosion is due to a pressure buildup. The thermite would have eventually melted a hole in that bucket, and molten thermite would have poured into that hole and into the ice, boring a hole in the ice right at that point. Now if this were water, the instantaneous steam being made would have bubbled out violently through the water and escaped. However, this is solid ice, and the large, ever-increasing amount of steam building in the ice hole has nowhere to go, with solid ice below it and molten thermite pouring in from the top sealing it up above, with the molten hot aluminum bucket acting as a gasket of sorts. This pressure builds up and has nowhere to go, until the ice cracks due to pressure and rapid temperature change, and all of a sudden the pressure is released in a dramatic explosion that sends everything flying. The aerosolized thermite may have been the cause of the fireball, but I don't believe that was the source of propulsion. There is a way to test my theory, if anyone is keen to try. Simply recreate the experiment, only use a pile of ground-up ice bits instead of a giant block of ice. If it is the aerosolized thermite or the hydrogen and oxygen ignition methods, then the increased surface area should improve the reaction rates and perhaps make a bigger boom. If my theory is correct, though, there will be plenty of room for air to escape, and we will see jets of steam flying off the ice pile instead of a sudden explosion.
I'm thinking this is *exactly* what happened - brilliant theory, I wasn't even thinking about the ice melting/vaporising. That would explain the sudden boom - the thermite gets through the bottom of the metal bucket, drips onto the ice, and that's when the ice gets vaporised (very suddenly because of the intense heat of thermite (3 times hotter that lava...) vaporises the ice instantly. The mythbusters' "hydrogen & oxygen split" idea is terrible - no energy released and no sudden kaboom, as you said; and the aerolised thermite idea is also terrible since it doesn't involve the ice - if it was that then we wouldn't need the ice, but we do.
this is correct. this is also why people are not supposed to let molten metals touch concrete. the water in the concrete instantly vaporizes, the vapor pressure inside the concrete causes the concrete to explode
My theory for why the ice explodes is sublimation, the thermite is so hot it instantly turns the the ice into gas, without ever turning into liquid form. This forms pockets of gas inside the bricks of ice and well when pressure builds up in something that has no room for gas. It goes boom.
That doesn't make any sense. The heat will have to go through the ice layer by layer, so the outside has definitely already either molten or sublimated before anything inside can be. Also, after the explosion the guy picks up blocks of ice that are completely intact.
The ice blew up due to thermal shock, ie Steam being instantly produced. As a steam engineer (7 years US Navy, working with boilers and turbines) That would be my best assessment.
Their thermite was red, meaning fe2o3. I If you get iron oxide as fe3o4 (bluish green) it burns a bunch hotter- I would be curious to see this replicated with that variant. FWIW, I think the first theory of the explosion is accurate- Molucular separation of some of the water. I use thermite to dispose of data on old hard drives (you can't recover data from a puddle...)
Alright, here's my theory on why you get an explosion. First, the thermite burns, and melts a hole in the galvanized steel bucket. Molten thermite starts to run out through that hole, and fills the cracks between the ice chunks with a mix of liquid iron, liquid aluminum, and some gaseous aluminum. This mixture does two things. Firstly, it causes the ice to melt and then vapourize. Secondly, all that steam in the presence of gaseous aluminum and molten iron is breaking into hydrogen and oxygen. Because it's in a confined space (trapped in the cavities between the ice chunks), the hydrogen and oxygen can't escape as quickly as they're being generated, and eventually enough builds up to create an explosion.
it would burn as it's being created though. If it were to have to cause an explosion, like jamie says, it would have to all be converted at once if you'd want enough hydrogen to cause an explosion.
Aluminium reacts with water much more violently then hydrogen+oxygen. its much more likely to be that causing it. when i say much more violently i mean MUCH more violently. even small amounts of molten aluminium+water would cause that exlosion
There is also another thing you could be is the pressure of the water vapor eventually get to high that causes it to explode its the same thing with casting its the instant vaporization causes it to pop.
Is this the same type of reaction you get when you drop water on hot oil on your stove? That can be pretty energetic on a smaller scale. Also, what sort of reaction would you get if you dropped a sizable block of ice on say molten lava?
My bet is the ice on lava wouldn’t do anything interesting. The water is denser than oil, so it tries to sink while vaporizing to steam, hence the rapid expansion of oil. Lava is exceptionally denser than water, either frozen or liquid. I think the ice sits on top of the lava boiling off.
It’s not the same reaction, what your describing is the Leidenfrost effect, when the water on a hot pan vaporizes and causes the vapors to move the water around. With magma something similar happens, when you drop something relatively wet in magma, it immediately vaporizes and causes the object to jump around the surface of the magma until it crisps up and then either turns to ash on top or melts into the magma. This would happen with human bodies too, the movies aren’t accurate. Instead of slowly sinking and melting in to lava, a body would bounce around on top like a bead of water until it loses all moisture. Terminator, busted.
I'm actually baffled why they couldn't understand what was happening. Thermite burns at roughly 2500°C, which is well beyond the boiling point of water (100°C) and where it turns into steam. The insane temperature would almost instantly vaporize the solid water/ice, turning it into steam in a fraction of a second and causing it to rapidly expand. Hence the explosion-ish effect. I'd wager that it comes down to a temperature differential between the ice having been almost instantly turned to steam (and hence expanding rapidly) and the the water still in its solid form. The myth "Exploding Jawbreaker" showed that a temperature differential could cause otherwise solid objects to explode and steam can release huge amounts of energy. After all, nuclear power plants are essentially turning water into steam and that steam is used to turn huge turbines.
you are partially correct. it seems to be the container material exploding due to extreme changes in pressure. as you already know, pressure is directly influenced by temperature.
I have a theory for what's happening here, but I haven't seen anyone explain it yet. Ok, so ordinarily, we think of water as a good way to put out a fire because it removes the oxygen supply. Thermite doesn't need an oxygen supply because the oxygen is provided by the rust, so that is moot. However, ice and water absorb a lot of heat when melting and boiling, so you would think they would still help contain the reaction rather than make it worse. Now, look up magnesium burning in Dry Ice. Magnesium DOES need oxygen to burn, so you would think encasing it in dry ice would snuff it. The thing is, the magnesium reactivity is high enough when burning that it actually rips the oxygen atoms off of CO2, leaving behind elemental carbon, and it continues to burn. Now, when the thermite reaction is taking place, you have aluminum powder oxidizing using the Fe2O3 as fuel, but what I'm thinking is what if Al at that temperature is reactive enough to pull oxygen off of the water? Is that possible? In that case, it would leave elemental hydrogen behind as a product, which could then react with oxygen in the air, or possibly with the FeO3. I don't buy the whole idea of steam forming in a pressurized area and then bursting out. The ice blocks are loosely stacked, with plenty of space for steam to escape between them, which is much easier than the steam trying to go through the reacting molten liquid pouring in from above it. I think there must be something going on chemically between the thermite and the ice.
For anyone still wondering, look up the Thunderf00t videos on why sodium or potassium explodes on contact with water. This explosion, along with the explosion you get from pouring molten sodium chloride into water are likely coulomb explosions like sodium, driven by electromagnetic forces rather than heat.
It happens the instant the molten metal melts through the bottom of the bucket. In that instant, you have a mass of extremely hot molten metal hitting the ice essentially all at once. You could test this by placing the bucket over a thick iron grill which will allow the molten metal to pour through it more slowly so massive amounts do not impact the ice all at once.
Newish development on the subject: it was the reaction of molten aluminum from the bucket with the water. Thermite is just there to liquidate the metal.
The hydrogen explosion hypothesis makes no sense. The energy released when you burn hydrogen is exactly equal to the energy required to split water in the first place. Unless the hydrogen is being stored somewhere, there's no way to get a sudden release of energy from decomposing water.
Steam takes up 1600 times the amount of space that ice does. The thermite burns so hot, it skips the phase change from ice to water, and goes directly to steam. Since the thermite will sink into the ice and start melting the inside, but not the outside, the steam has NO place to go, and will explode out with that kind of violence. A MUCH smaller scale of the same reaction is to put a coke can in the freezer. Solid water takes up a bit more space than water (due to the hydrogen bonding of water), and causes the can to "explode". Same principles though, pressure can do magical things :)
+Dillon Donnelly the pressure rise would be do dramatic and explosive, the relatively small hole wouldn't matter a whole bunch. you can do this experiment at home to see. get a sewing needle and a large ice cube. heat the needle with a torch and slide it inside the ice cube. it will crack and explode out ( albeit with much less force). the other guy may be correct about the hydrogen being stripped from the water molecules and becoming an explosive gas, but thats pretty dubious
It is really cool that back in 2009 we did not understand why this happened, but now we do. This is an example of a columbic explosion. A common misconception is that it is a result of the rapid production of steam, however if you try it with a non conductive substance like molten glass you don't get the explosion, only a conductive substance will work.
on rly the reaction its simple ... some fire extinguishers use water ... in a fire of class D (special class) its some metals can explode in reaction with H2O ... the thermite enter in this class D ( you NEVER can user water on thermite ) because the temperature its too hight to divide Hidrogen and the oxygen ... transforming it on a very very very powerfull feed for the reaction of the fire .... thermite on ice its the same thing ... the ... it cause the explosion ... shadered H2O transform in atoms of Hidrogen and Pure Oxigen ! cause a very powerfull explosion when ignited ! ^^ (im tecnic in work security) ^^
"It's a mystery - we don't know" Oh my gaaaawd just CALL a university and ask for a physicist. You can't just leave things "unknown". If you don't know get someone who does.
KhazWolf Yes, But as a chemist myself my application for physics is little to none as a physicist does not use/know chemistry as well as I. That is why it is 2 separate jobs and why both occupations focus on different things "Chemistry is the Central Science"
KhazWolf You're so stupid! What was the point of that picture. There is a reason why a physicist is called a physicist and a chemist is called a chemist. Anyways that website was about sarcasm. As a chemist in academia I think I know this better than you.
It's called a Phreatic Eruption or Phreatic Explosion, it happens in volcanoes all the time. The thermite is burning at approximately 2,200 degrees Celsius (around 4,000 Fahrenheit.) It's so hot that the ice directly under the bucket (because the thermite burned downward through the bucket and only came in contact with that ice) instantly turns to super-heated steam, and creates a steam explosion which is what shot the rest of the ice fragments everywhere.
Doesn’t explain why it explodes with ice and not water. You can drop thermite in water and it will continue to burn creating lots of bubbles but no explosion, I’ve seen it.
@@brett7406 This is just a guess, like they say in the video no one knows for sure due to lack of studies. They're not even sure if this is a chemical or physical reaction (or both).
One thing I'm thinking about is that when you drop an ice cube into a glas of bioling water then it always cracks with a loud noise. Maybe that's a smaller reaction of this?
Not quite, when ice cracks in warm water it's due to the outer surface of the ice ice expanding faster than the inside. In fact, since no new substance is acutally formed, it's not even a chemical reaction.
Pianoguy32 No1 knows for sure but the current theory is nano-thermite. Thermite residue was found throughout the wreckage at the bottom of the tower and you can see quite clearly on the videos white smoke come out just before it collapsed but if it was smoke from a fire it would have been black due to lack of oxygen
We were taught about, but not allowed to try, this on the Norwegian oil rig safety training back in the 80s. We were warned never to use water to put out a burning metal fire as exactly this would happen. Basically the burning metal of the bucket will be so hungry for oxygen that it will split the water leaving hydrogen which builds up until it explodes. That's where the bucket went, it simply burned away. It's a little like oxy-acetyline cutting. Once you have the steel burning you can apply pure oxygen and it will go much faster.
The center was hottest, created enough heat for the center to separate the two gases, building enough pressure to crack the outside shell. But that would have to go through the top shell somehow, unless it happened too fast for us to see it melt the top off quickly enough, it drops in, and the outside shell cracks.
To this day, I still don't understand why they went to a former FBI agent for explosives, and not an ATF one. Since the ATF's real acronym is BATFE and the E is for explosives...
My guess is something along the lines of a grease explosion. Dump grease into boiling water, it ignites, causing the water tonturn to steam, carrying greas particles with it, the now superheated grease is exposex to much more oxygen and explodes rather than a simple ignition. Same thing's happening to the thermite. Some of it's getting tossed around out of the fire, some of the ice is sublimating directly to steam, picking up particles of thermite, at the same time, the fire is melting through the bucket, alongside a steam buildup underneath, leading to both explosive decompression, and a dust explosion fueled by thermite. Which explains the two simultaneous explosions seen on the temperature view.
I agree but with the following added, the vapor is within the ice and the gas expands until it's container (the outer wall of ice) can no longer hold and the ice explodes.
The vapour isn't in a sealed container, so it can't build up the pressure on its own. However, the rapidly expanding vapour can scatter the thermite powder, as soon as the bucket fails, thermite goes everywhere, allowing it to mis with air faster, and thus burn faster, and there's the boom.
Yes, water vapor is not explosive by itself, but the heat converts ice into water vapor in a couple of milliseconds. Water vapor occupies a VERY LARGE volume compared to ice. This sudden expansion is the cause of the explosion (just like when a bomb goes off).
It comes down to this it’s a high-pressure steam explosion, depending on how evenly the thermite pours over the ice depends on how powerful the explosion is
It's simple hot and cold liquids. Thermite burns at over 4500F. With enough of it that's hot enough to turn ice to steam in microseconds = explosion. You get a similar effect taking a glass of water and pouring it in a 100-ton kettle of 3000F molten steel or other metal (bad idea, molten metal will fly everywhere just like in the video). Also happens when hot lava hits the ocean in Hawaii. They really should take a 100,000 fps video of this so the thermite touching the ice and melting it and watching the resulting steam blow apart the remaining ice and bricks and turning them into projectiles can be easily seen.
***** You're not incorrect, however, that will cause burning, not an outward explosion. The water reaches its triple point well below the temperature of thermite at STP. To challenge what you're thinking, check out the volume difference of steam and ice. Very likely this was a pressure explosion with some slight burning from the hydrolysis. The explosion was physical reaction, not a chemical.
***** Not necessarily, super heated steam has no "vapor" to speak of, its perfectly clear. it's entirely possible by the time it condensed it was spread out enough to not see any steam cloud.
The slightly heated thermite at the bottom of the bucket condenses due to the cold ice underneath. When the flame finally reaches the condensed thermitet the thermite expands rapidly and EXPLODES.
thermite reaction is at a very high temperature, it creates liquid iron (iron oxide is a main component in thermite) molten iron melts aluminium bucket bottom, melts though ice creating steam, the deeper it goes - the more ice is turned into steam (lidenfrost effect) and more steam there is = more pressure built up in the cavity in the ice. hence the explosion...
en.wikipedia.org/wiki/Steam_explosion Metal fires are usually left alone by firefighting teams unless absolutely necessary. In those cases, dry sand is used to create a barrier between the fire and atmospheric water vapor to prevent a steam explosion. Vitrified sand (glass) on a fire is safer than having it explode and then rain burning metal over a large area.
Steam won't do a thing, because it won't have the pressure. Look at how slowly the ice melts. You can calculate the amount of steam generated. Since it's not in a confined space, it wouldn't build much pressure, certainly not enough to produce such a boom. Meanwhile the temperature of the burning thermite is far than enough to split water molecules, which produce oxyhydrogen, a volatile gas which can explode even unconfined. Also, more oxygen will not make thermite burn faster or explode.
It's the rapid expansion of steam from the ice. The thermite gives the ice so much energy it immediately vaporizes, causing an explosion so long as it remains in contact with the ice. Which, of course, is why it was so short and the ice was blown away preventing it to become any bigger.
yes I know. normally the Leidenfrost effect is done on a hot plate with a cold vaporiseble drop but here its the other way round. your theory could work if it was a solid block of ice and even then the flower pot would need a perfect seal and weigh several hundred pound. that lot can't way more than 4 so the pressure need to knock the bucket of would be quite low.
If you're turning ice into steam over a few Seconds then it won't go boom. It has to be in a few milliseconds if not microseconds to get that kind of reaction only from the ice. Most likely the explosive power came from the thermite
Anju Maaka nope, except the time span ascdren is right.. at an atmospheric pressure of 1bar water freezes at zero centigrade and boils at 100 centigrade.. A thermite reaction has well over 2000 centigrade.. so you have to overcome 100 with 2000+ celsius.. i'm confident thats instant explosion..
It is great how they did not expect the thing to explode. They always do the blast screen, but when they expect a real explosion they do the bunker. And the camera would not stand around but would be a remote controlled one…..
Thermite works via a transfer of oxygen between metals, normally iron oxide + aluminum to aluminum oxide and molten iron. Normally an aerosol of flammable materials is more explosive, but this is because it needs the oxygen from the air for the reaction. This is not the case for thermite reaction. The reaction is readily explained with basic chemistry. What is happening is that the aluminum powder is reacting with the steam. 2Al + 3H2O -> Al2O3 + 3H2. This by itself would not cause the explosion but the hydrogen produced is mixed with the oxygen in the atmosphere and ignited by the thermite. The effect would be even stronger if the ratio of Aluminum powder was greatly increased in the thermite mix.
It is a textbook flash steam explosion, the thermite burns hot enough that it skips over the liquid state of water causing the solid to expand directly into a gas
I assumed is was like what happens when you pour hot water into a cold glass dish, it cracks or explodes. Since cold tends to condense molecules and heat expands, I assume that the rapid super heating is expanding the ice so quickly that it acts like a pipe-b, which is to say that it acts under intense pressure from the rapid expansion and shoots the fragments everywhere.
when the flame front hits the colder thermite, the force of the already burning warmer thermite escaping from the top of the tin bucket pushes down on the remaining thermite compressing the air, moisture and thermite. once the cooler thermite ignites it burnes far more ferociously due to the containment/pressure and also due to being enriched with oxygen as it cooled (cool=vacuum etc). just like containing other flamables and igniting them makes them explosive, this enriched slightly (MORE)
The FBI guy at 0:39 looks the the human version of Grumpy Cat.
Corristo89 I thought he looked like Walter from Achmed the dead terrorist!
I know that you're talking about people looking like grumpy cat in this post but I have the explanation for it exploding. You all know how sometimes ice will crack when you put it in water, well the explosion is that on a more extreme, large scale. Heat + ice = cracked or melted ice, depending if it was slowly exposed (melting) or if it was instantly introduced to the heat (cracked). If it was instantly introduced to the heat it wouldn't have time to react (melt) so it would crack. In this case it would be exposed to extreme heat almost instantly leaving no time for it to melt or give off steam and since it isn't just a little warmer like water it would crack and trying to distribute the heat but in this case there is too much for it to distribute and not enough time so it would just explode into a bunch of little pieces. To prove this just look at the ice left over, does it look melted or torn? And the truth is that is was torn not melted otherwise it would be smooth.
***** Jeff Dunham
Flyin Good Agreed!
Corristo89 JeffDun-HAM
"I think they've done something a little iffy." :c
Will Flock :c
+Will Flock :c
+Will Flock Just a little *IFFY*
:C
+Amy :С
holodilnikusone Your name is a little...
*IFFY*
:C
I really like Jamies sections on this show, he strikes me as a man who is half soldier half scientist.
half wit too.
Andrew Baddeley ooooooooooo burn
...and 100% walrus.
Well he’s working for the Navy / darpa now
So he's ratchet from transformers lol
This is hardly a mystery.
Any foundry or steel mill worker will tell you that molten iron (like one gets from Thermite) will often incapsulate moist, water and ice on contact, resulting in a gas explosion.
That's just a hypothesis. It's possible, but not a definite
I thought the same. The ice submilates quickly and the created gas expands.
I thought that too but I’ve seen videos where thermite is dropped directly into water and it doesn’t explode. The slo Mo guys did a video on it I think.
@@brett7406 thats because its water genius, water has almost 0 resistance and moves out of the way, ice does not.
thermite burns so hot that it splits the water into hydrogen and oxygen, which has nothing to do with iron, it's just a question of the heat
I think I like it better when they confirm internet videos then bust them. By default I am expecting an internet video to be a fake so it is nice to see a real one.
Actually it's not just a speculation that thermite decomposes water to oxygen and hydrogen. It does. That's why steel works have safety rules against bringing anything wet (including water) near the furnaces or molten steel.
Not at all. It doesnt do this at all - why should it? its about boiling the water within the ice block and casuing it to explode.
@@halsosabowski2400 Yeah im guessing once the molten iron cools down enough the molten metal contacts the ice and creates a ton of steam at once and BOOM.
I was taught the thing about hydrogen aswell when working at a steel plant. They left the gates open in the winter due to the explosions being very frequent when there was snow on the recycled steel from outside. We also used electrodes to melt the steel and that might have something to do with it aswell.
Hydrogen with air mixed in the open does not detonate.
@@halsosabowski2400 I agree with you on the flash boiling hypothesis. I think the reaction melts the top block of ice, and when the molten metal drops into the water it causes the water to flash boil.
I think they are forgetting the very definition of an explosion: rapid expansion of gases.
You are vaporizing 0C water at 2500C in an instant, what do you expect to happen?
I was gonna leave an answer... but you've said it.
Boom = shock wave = rapidly expanding gas
really really hot water vapour result in the destruction of the water molecula in dihydrogen and oxygen then fire + dihydrogen + oxygen = boom ...... didn't you know guys ?
Nero Lostshor stop trying to sound smart?
quelorepario dry ice is not water so there is no hydrogen in C02. However there is fuel=Carbon, Oxygen and heat=thermite so it could exploded based on those three components. The thermite through an exothermic reaction could separate the Carbon and Oxygen. This is cool.
CrismaFire they never said dry ice, only ice
Best explanation I got: That termite is burning at around 2500C, which is 25 times waters boiling point. What happens is that the second that the bucket gives way to the thermite, the ice transitions directly into steam (vaporization). Vaporization is a very energetic process, so it makes sense that it would create a blast the way it did.
If this hypothesis is correct, the same (or better) result should be with dry ice.
Not being a pedant but, since I like using the word when I can cause it's fun, when solid turns directly into gas it Sublimates
@@tiptapdrats8454 It is a delicious word
2500C is ~7.5 times hotter than the boiling point of water, not 25 times. You have to use Kelvin
@@blackmagicprod7039 The boiling point of water is 100 degree C by definition (that's who the Celsius scale is defined: 100 water boils, 0 water freezes). 2500 is 25 times 100.
Stick a giant bucket of thermite on top of a glacier. What would happen?
There's only 1 way to find out :)!
krammy999999 Fight!
The polar ice caps would get that much smaller.
kardinmo I... don't think you quite understand how this chemical reaction works.
Not much i think. The thermite is needed to make the explosion. Unless you drop like 200 m3 of thermite, almost nothing would happen
The FBI agent looks like a doll used by Jeff Dunham
+Seth Woodruff Just a little *IFFY*
:C
+Seth Woodruff my name jeff.
+Seth Woodruff You mean Walter, the grouchy old man? "Welcome to Mythbusters. Do your explosions, and get the hell out! Have a nice day."
he looks like judge dredd
He looks like the old guy from up
Steam explosions act just as you say, but some metals can either chemically react with the H and O or cause High-temperature electrolysis. The stated temp for HTE and the burning temp of thermite are both given to be ~2500C. If HTE occurs, then what Jamie describes at 3:17 is exactly what is happening (after the initial steam explosion).
I think they've done something a little iffy >:C
I think one of them farted, which caused his face to contort while talking
I think it's a mixture of the water vapor, and jamie's aerolisation theory. The thermite is a powder that's on top, burning downward. When the water melts and turns to steam, it will go the path of least resistance, namely straight up and through the powder. This will carry lots of thermite powder up, which then all ignites together. Probably something like a dust/flour explosion.
A song of ice and fire...
Hopefully FBI guy put a little more thought into all of the investigations he was involved in.
How many thermite related crimes do you think he investigated?
>:c
Considering expert scientists aren’t quite sure how the thing they’re doing is happening, I think we can forgive him for being a little ignorant on this one.
Corey I’m talking about 3:11, where the narrator and Jamie say the experts they talked to weren’t quite sure how the reaction was happening. I am currently at Uni for my Bachelors in Physics. Scientists constantly work on problems and experiments where they aren’t sure of the outcome or reasons behind an effect. Everything that is understood becomes a thing to study while scientists’ real focus is in the unexplained. If we understood how everything worked, there would be no need for scientists, but just people who knew things.
Corey “Experts” is open to interpretation and I would hope they were talking to professors in thermodynamics (maybe what you mean by explosives experts), but I don’t think they were consulting bomb technicians. I think I’m using the word “know” differently to how you do. I don’t know what your background is, but the language I hear about experimentation is “suspicion of an outcome” or “reasonable model for application to a scenario”. To know something means the experiment has already been done multiple times with peer review. The scientists I work with are the first to say they don’t “know” if an experiment will go the way the theory stated. To do so would be sort of arrogant. And experiments involving unknown conclusions have about a 2/3rds chance of going with the expected outcome.
0:48 his face xD "something a little iffy x( "
Wait a minute. This is a thermite reaction. We have a buttload of oxidation going on, and a temperature high enough to split water, so not only will we expect a Hydrogen explosion, but the extra Oxygen present would drive the thermite reaction into a rapid oxidation of both metals as well, increasing the temperature. There's your positive feedback loop.
I'm not convinced of that explanation
For that to happen, the H & O2 need to be in close contact and in the right concentration. Unfortunately, there's no containment vessel preventing the H & O2 from dissipating.
You are essentially describing an endothermic and an exothermic process with the same energy somehow releasing a boatload of energy. They would just cancel each other out. Water decomposes, decomposed elements turn into water again. Somehow explodes. How does that make sense? You are putting in energy to decompose the water, then you are releasing that same energy when the water recombines. This sort of thing can lead to an explosion when there is a long enough delay where the gas mixture simply accumulates before going up all at once but that simply isn't what we saw here.
Actually they do. For instance time to time a stray WW2 bullet ends up in the scrap metal and pops.
The camera work and editing on this video is a work of art. They perfectly get the explosion, the reaction, and showed every angle when it needed to be shown.
Could we get an Adam and Jamie OnlyFans page?
Couse its a profesional camera, not a potatoe used for making "UFO spoted movies"
I mean, it was a professionally produced TV show
@@prasaite true
This video gives a completely new meaning of "The song of Ice and Fire" ❄️🔥
I miss them, I know there's supposed to be a reboot but it won't be the same.
Speaking from my experience with hydrogen dissociation in retort tube furnaces, it's more than possible. The furnaces I work with only get up to about 2000 degrees Fahrenheit, but they dissociate a little less than a pint of water per minute, which translates to around 1000 cfm of hydrogen and oxygen. If our burnoff stacks go out, catastrophic levels can build up in seconds.
Matthew Miller don't use farheneit
A good control test would have been to substitute dry ice for ice. You would still have the vaporization and volume increase but you eliminate the possibility of H2O-> H2 and O2 -> to H2O.
I suspect what happened is that the heat of the thermite caused the water inside the ice to boil fast enough to a high enough heat as to make the resulting high-pressure steam blow apart the ice blocks.
Just like how a meteor explodes before it has a chance to impact. A lot of ice and a lot of heat!
Seems the most likely explanation, plus once the high pressure steam blows the thermite into a "cloud" that would burn rapidly too making the explosion even bigger.
CreeperOnYourHouse He kind of said that at 3:20
Terence Person No, they said that the thermite somehow turned the water into hydrogen and oxygen, which then rebonded and exploded.
I'm saying that it's high-pressure steam.
CreeperOnYourHouse Exactly, what does hyrdrogen and oxygen make? H2O what is H2O you ask? Water.
This is the myth that surprised me the most, I didn't think that thermite could flash ice into steam fast enough to cause an explosion
I'm just watching this thinking
"Huh, Jamie really does look like Thermite from Rainbow 6 Siege"
Im genuinely amazed that not one of them thought it could be a steam explosion
it seems a lot of people in the comments thinks that it's steam related but I think Jamie's reasoning (although not intended towards steam) holds true. To get a steam explosion you must build pressure then quickly release it, there is no way for pressure to build in an open system like this so it seems very unlikely to be a steam explosion. The best explanation I can come up with for why it could be a steam explosion is that the thermite quickly burrows a channel into an ice block where it sublimates a spherical cavity. meanwhile, the molten iron/aluminum/steel bucket/water have plugged the entrance to the cavity allowing it to begin holding pressure, resulting in a steam explosion. I have no clue if that's true though
ok i was curious so I googled it and someone did their masters thesis on it! Look for The phenomenon of exploding ice - conditions and explanations by Valmadre, Dominic (2016). Here's a portion of the abstract of the essay:
"It was found that the explosion in question was most comparable to a boiling liquid expanding vapour explosion. The thermite reaches a molten state and penetrates through the bucket in which it was stored. Then, it flows into the core of the ice block where it creates a pseudo short-term pressure vessel. The standard thermite redox reaction continues to occur within the icy chamber causing a localised increase of pressure and a liquid-vapour equilibrium to arise.
After a few seconds, the icy shell ruptures, resulting in a rapid loss of the localised pressure as it reduces to the atmospheric pressure. A small splutter will occur at this stage as water vapour and droplets are expelled from the system. After the system equalises, a volume of superheated water will exist that will then violently evaporate from 0.0144 m3 of water to 19.6160 m3 of water vapour. The remaining ice shell shatters in a brittle manner and the rapid gas expansion is the driving force of the observed explosion.
In chapter 5, illustrations of this process exist in a set of steps that clearly demonstrate the phenomenon. The findings of this project were significant as it was discovered that, with the exception of the exothermic thermite redox, the explosion was driven by purely physical means and without chemical reaction. "
@@mantissa182 you can get a steam explosion in open air, you just need enough heat flash vaporizing ice into steam. It's like how if a even a couple drops of water gets in an open foundry it will cause a steam explosion that will send molten metal all over.
There should be a fairly easy way to test the two theories offered by Jamie at the end of the video for why the explosion occurred. Assuming that it is one of the two, then you could try the experiment with varying amounts of ice and thermite. If increasing masses of ice produces a higher yield explosion, then it is likely that the 2H2 + O2 being ignited is responsible for the explosion. If increasing masses of thermite produces a higher yield explosion, then it is likely that eitehr the thermite is being aerosolized or that the ice is in some way influencing the thermite as opposed to the thermite influencing the ice.
You'd think an explosive expert would know what happens when intense heat meets ice.
I'm surprised that they did not suggest that once the thermite melted through the base of the bucket and was completely encased in ice, it quickly vaporised a large amount of water (Because thermite is 3 times hotter than volcanic magma) which would then carry any remaining powdered thermite, as well as much of the molten thermite into the air. This can happen because the melting ice would create a water barrier that would not allow the gasses to escape fast enough out the sides so it would attempt to go up, unfortunately that would be blocked by 10 lbs of molten thermite and so once the core of the block (which is now boiling water) flash boils, the massive expansion of gasses would push everything out very violently
Would not the ice turn instantly to gas at those temperatures? And is not it this gas sealed by the molted iron/higher temperature of reaction of the bucket which is above it?
Bart Hoving
The water doesn't go instantly from below freezing to above boiling. It takes time to transfer the heat energy, so the ice needs to melt before it can boil.
Mikkel Højbak the point is that at those extreme temperatures the transition is so fast there is no time to build up fluid. In all practicality it is instantly turned into gas. Damn termite melt through iron almost instantly like it is butter, and iron melts at 2000 degrees Celsius and can hold more heat energy than water. I'm sure the termite has no problem at getting the ice up to 100 degrees Celsius almost instantly, in fact I'd be surprised if it didn't.
Sure, there is no buildup, since the water boils just as fast as the ice melts. That doesn't mean that it skips the liquid phase (sublimation), though. There is just very little liquid at any one point in time.
My thoughts on the reason for the explosion: The very first thermite to hit the ice block will most likely be cooled down enough to transition back to the solid state, effectively encapsulating the ice in a thin layer of solid metal. The now very hot, confined steam inside will then eventually burst the surrounding ice through the buildup in pressure.
Mikkel Højbak I think it is just the opposite, I think that the water that is trying to escape out the sides and top freeze in the cracks between the blocks to create that seal. then maybe something similar to what you said blocks off the top. but this whole thing is incredibly complex, so it is tough to say for sure... next time they should put a gopro inside the ice to watch and see what happens.
0:32
Said Sega Of America.
xD
for people who dont get it . Sonic Boom - Fire & Ice for the 3DS
HAHAHAHAHA
Hahahaha This is rediculously funny. Maybe it's just my age showing.
You know how ice cracks when you put it in your drink?
I remember watching a documentary on the building of ice hotels, and how they had to make sure the ice did not heat up as they worked with it. The ice could crack and "explode" (as they put it) because of how compressed ice blocks are.
Perhaps the same thing is happening here. The ice blocks are heating so quickly that they explode into chunks of ice. That would explain the force, but not the glowing particulates.
The glowing particulates would be the bits of burning thermite being thrown about.
That fbi dude is literally thermite from rainbow six siege when he’s 70 😂
0:48 I like his face. Reminds me of Walter from Jeff Dunham.
concealed gunpowder **facepalm**
its just rapidly expanding steam causing a "explosion"
+MrAWESOMElol2
Nope. It's a coloumb explosion.
+MrAwesomelol2 actually no its a Coulombic explosion
just looked it up on wikipedia....how the fuck is that supposed to be a coloumb explosion
From wikipedia: "High speed camera imaging of alkali metals exploding in water has suggested the explosion is a coulomb explosion.[3][4]". www.nature.com/nchem/journal/v7/n3/full/nchem.2161.html
Not sure I'm convinced aluminum has that same behavior.
Now, we know aluminum does react with water, typically "slowly", producing hydrogen. Maybe the huge surface area of the aluminum dust coupled with (almost pure) water vapour helps the reaction happen quickly.
I think this is very interesting because it seems that maybe there's more than one factor contributing to the "explosion". But maybe it's really just steam and nothing else.
Either way, to check out if the water contributes much to the reactivity of the whole thing, you could do the same experiment using dry ice. The molar volume change of dry ice is very similar to (water) ice, so the expanding gas/steam factor should be about the same.
What's so hard to understand. Thermite gets extremely hot very quickly once ignited. The gas simply can't escape fast enough from the ice; therefore, boom. It's no different if you throw a frozen steak on a hot pan with vegetable oil inside it. It pops.
Either method seems limited by the fact that there would be no accumulation and thus no sudden boom. There is no container keeping hydrogen and oxygen contained, and there is constantly enough of an ignition source from the very beginning of the possibility of water splitting. So if it was this method, they would "explode" just as fast as they were being separated, making a strong steady burn instead of an explosion. The aerosolization method seems more plausible, if the conversion of ice into steam is that dramatic. However, the explosion seems to have originated at the base, right at or within the ice. There doesn't seem to be enough room for all that thermite to be aerosolized like that directly under the bucket. More importantly, if you look at the infrared vision, you'll see that some thermite had already made it down to touch the ice on the side, exposed to air, and there was no explosion there. There was plenty of clouds of fire spraying off the side, which could well be due to aerosolization, but it was not nearly violent enough to create this kind of shock wave explosion.
My guess is that this is very similar to their microwaved jawbreaker experiment, and that this explosion is due to a pressure buildup. The thermite would have eventually melted a hole in that bucket, and molten thermite would have poured into that hole and into the ice, boring a hole in the ice right at that point. Now if this were water, the instantaneous steam being made would have bubbled out violently through the water and escaped. However, this is solid ice, and the large, ever-increasing amount of steam building in the ice hole has nowhere to go, with solid ice below it and molten thermite pouring in from the top sealing it up above, with the molten hot aluminum bucket acting as a gasket of sorts. This pressure builds up and has nowhere to go, until the ice cracks due to pressure and rapid temperature change, and all of a sudden the pressure is released in a dramatic explosion that sends everything flying. The aerosolized thermite may have been the cause of the fireball, but I don't believe that was the source of propulsion.
There is a way to test my theory, if anyone is keen to try. Simply recreate the experiment, only use a pile of ground-up ice bits instead of a giant block of ice. If it is the aerosolized thermite or the hydrogen and oxygen ignition methods, then the increased surface area should improve the reaction rates and perhaps make a bigger boom. If my theory is correct, though, there will be plenty of room for air to escape, and we will see jets of steam flying off the ice pile instead of a sudden explosion.
Great theory, i say we need a test to be sure.
If the facts don't fit the theory, change the theory.
I'm thinking this is *exactly* what happened - brilliant theory, I wasn't even thinking about the ice melting/vaporising. That would explain the sudden boom - the thermite gets through the bottom of the metal bucket, drips onto the ice, and that's when the ice gets vaporised (very suddenly because of the intense heat of thermite (3 times hotter that lava...) vaporises the ice instantly.
The mythbusters' "hydrogen & oxygen split" idea is terrible - no energy released and no sudden kaboom, as you said; and the aerolised thermite idea is also terrible since it doesn't involve the ice - if it was that then we wouldn't need the ice, but we do.
this is correct. this is also why people are not supposed to let molten metals touch concrete. the water in the concrete instantly vaporizes, the vapor pressure inside the concrete causes the concrete to explode
My theory for why the ice explodes is sublimation, the thermite is so hot it instantly turns the the ice into gas, without ever turning into liquid form. This forms pockets of gas inside the bricks of ice and well when pressure builds up in something that has no room for gas. It goes boom.
That doesn't make any sense. The heat will have to go through the ice layer by layer, so the outside has definitely already either molten or sublimated before anything inside can be. Also, after the explosion the guy picks up blocks of ice that are completely intact.
The ice blew up due to thermal shock, ie Steam being instantly produced. As a steam engineer (7 years US Navy, working with boilers and turbines) That would be my best assessment.
The ice sublimates into steam, this rapid expansion causes the explosion, much like the moisture in a kernel causes it to pop.
Their thermite was red, meaning fe2o3. I If you get iron oxide as fe3o4 (bluish green) it burns a bunch hotter- I would be curious to see this replicated with that variant.
FWIW, I think the first theory of the explosion is accurate- Molucular separation of some of the water.
I use thermite to dispose of data on old hard drives (you can't recover data from a puddle...)
"There's no trace at all of the steel bucket." You can clearly see it behind them next to the wall at 3:05 :p
late response but it is the second thermite mixture in case something goes wrong
In 3:30 you can see that the bucket got shredded and a piece flew into the glass.
That's the ice, not the bucket
Separate container.
Alright, here's my theory on why you get an explosion. First, the thermite burns, and melts a hole in the galvanized steel bucket. Molten thermite starts to run out through that hole, and fills the cracks between the ice chunks with a mix of liquid iron, liquid aluminum, and some gaseous aluminum. This mixture does two things. Firstly, it causes the ice to melt and then vapourize. Secondly, all that steam in the presence of gaseous aluminum and molten iron is breaking into hydrogen and oxygen. Because it's in a confined space (trapped in the cavities between the ice chunks), the hydrogen and oxygen can't escape as quickly as they're being generated, and eventually enough builds up to create an explosion.
It's the same thing as throwing meat into lava
it would burn as it's being created though. If it were to have to cause an explosion, like jamie says, it would have to all be converted at once if you'd want enough hydrogen to cause an explosion.
Aluminium reacts with water much more violently then hydrogen+oxygen. its much more likely to be that causing it. when i say much more violently i mean MUCH more violently. even small amounts of molten aluminium+water would cause that exlosion
There is also another thing you could be is the pressure of the water vapor eventually get to high that causes it to explode its the same thing with casting its the instant vaporization causes it to pop.
Chemistry ftw
Is this the same type of reaction you get when you drop water on hot oil on your stove? That can be pretty energetic on a smaller scale. Also, what sort of reaction would you get if you dropped a sizable block of ice on say molten lava?
My bet is the ice on lava wouldn’t do anything interesting.
The water is denser than oil, so it tries to sink while vaporizing to steam, hence the rapid expansion of oil. Lava is exceptionally denser than water, either frozen or liquid. I think the ice sits on top of the lava boiling off.
It’s not the same reaction, what your describing is the Leidenfrost effect, when the water on a hot pan vaporizes and causes the vapors to move the water around. With magma something similar happens, when you drop something relatively wet in magma, it immediately vaporizes and causes the object to jump around the surface of the magma until it crisps up and then either turns to ash on top or melts into the magma. This would happen with human bodies too, the movies aren’t accurate. Instead of slowly sinking and melting in to lava, a body would bounce around on top like a bead of water until it loses all moisture. Terminator, busted.
I'm actually baffled why they couldn't understand what was happening. Thermite burns at roughly 2500°C, which is well beyond the boiling point of water (100°C) and where it turns into steam. The insane temperature would almost instantly vaporize the solid water/ice, turning it into steam in a fraction of a second and causing it to rapidly expand. Hence the explosion-ish effect. I'd wager that it comes down to a temperature differential between the ice having been almost instantly turned to steam (and hence expanding rapidly) and the the water still in its solid form.
The myth "Exploding Jawbreaker" showed that a temperature differential could cause otherwise solid objects to explode and steam can release huge amounts of energy. After all, nuclear power plants are essentially turning water into steam and that steam is used to turn huge turbines.
So by this logic, doesn't that mean ANYTHING would explode as long as the contrast in temperature is big enough?
+RedHairdo yeah thats why a volcano wouldnt semi-erupt if you fell in
+RedHairdo no.. that's not the logic at all.. all he is talking about is a steam explosion, you can look it up if you want.
+RedHairdo no.. that's not the logic at all.. all he is talking about is a steam explosion, you can look it up if you want.
you are partially correct. it seems to be the container material exploding due to extreme changes in pressure. as you already know, pressure is directly influenced by temperature.
Dear creators of Game of Thrones,
this is how I'd like the meeting of Dany and Jon to go down.
Hate to break ti to you...
I have a theory for what's happening here, but I haven't seen anyone explain it yet. Ok, so ordinarily, we think of water as a good way to put out a fire because it removes the oxygen supply. Thermite doesn't need an oxygen supply because the oxygen is provided by the rust, so that is moot. However, ice and water absorb a lot of heat when melting and boiling, so you would think they would still help contain the reaction rather than make it worse.
Now, look up magnesium burning in Dry Ice. Magnesium DOES need oxygen to burn, so you would think encasing it in dry ice would snuff it. The thing is, the magnesium reactivity is high enough when burning that it actually rips the oxygen atoms off of CO2, leaving behind elemental carbon, and it continues to burn. Now, when the thermite reaction is taking place, you have aluminum powder oxidizing using the Fe2O3 as fuel, but what I'm thinking is what if Al at that temperature is reactive enough to pull oxygen off of the water? Is that possible? In that case, it would leave elemental hydrogen behind as a product, which could then react with oxygen in the air, or possibly with the FeO3.
I don't buy the whole idea of steam forming in a pressurized area and then bursting out. The ice blocks are loosely stacked, with plenty of space for steam to escape between them, which is much easier than the steam trying to go through the reacting molten liquid pouring in from above it. I think there must be something going on chemically between the thermite and the ice.
For anyone still wondering, look up the Thunderf00t videos on why sodium or potassium explodes on contact with water. This explosion, along with the explosion you get from pouring molten sodium chloride into water are likely coulomb explosions like sodium, driven by electromagnetic forces rather than heat.
It happens the instant the molten metal melts through the bottom of the bucket. In that instant, you have a mass of extremely hot molten metal hitting the ice essentially all at once. You could test this by placing the bucket over a thick iron grill which will allow the molten metal to pour through it more slowly so massive amounts do not impact the ice all at once.
“Hears and sees explosion instantly grabs hat”
Newish development on the subject: it was the reaction of molten aluminum from the bucket with the water. Thermite is just there to liquidate the metal.
RomanQrr yeah water + thermite = big boom
Except its a Galvanized Steel Bucket. Not Aluminum
The hydrogen explosion hypothesis makes no sense. The energy released when you burn hydrogen is exactly equal to the energy required to split water in the first place. Unless the hydrogen is being stored somewhere, there's no way to get a sudden release of energy from decomposing water.
en.m.wikipedia.org/wiki/Oxyhydrogen
ice explodes if you pour molten metal on it
Alpha Beta no, lava just hovers over it.
Steam takes up 1600 times the amount of space that ice does. The thermite burns so hot, it skips the phase change from ice to water, and goes directly to steam. Since the thermite will sink into the ice and start melting the inside, but not the outside, the steam has NO place to go, and will explode out with that kind of violence.
A MUCH smaller scale of the same reaction is to put a coke can in the freezer. Solid water takes up a bit more space than water (due to the hydrogen bonding of water), and causes the can to "explode".
Same principles though, pressure can do magical things :)
its true and same goes for explosions in industry when molten metal is accidentally poured over watet
How is that? If the thermite had burnt a hole through the ice, wouldn't the steam just escape through said hole?
+Dillon Donnelly the pressure rise would be do dramatic and explosive, the relatively small hole wouldn't matter a whole bunch.
you can do this experiment at home to see. get a sewing needle and a large ice cube. heat the needle with a torch and slide it inside the ice cube. it will crack and explode out ( albeit with much less force).
the other guy may be correct about the hydrogen being stripped from the water molecules and becoming an explosive gas, but thats pretty dubious
+JgHaverty This is what I was thinking - pressure building up so quickly that it explodes.
Could be the ice melting so fast that a steam explosion occurs
yes its literally sublimation
I feel like the bucket is violently seizing between the heat and cold.. anyone else agree?
0:39 look at that smile
"I am a believer!"
bain:did anyone get that second can of thermite?
+Oreodogify Guys The Thermal Drill Go Get It :v
Chains is adding muriatic acid.
lel references
Jamie puts on an entire fire suit except the fire glove for the hand that he's using to light the fuse...
And not fully zippered up the front before putting on the hood. You can see his green shirt.
It is really cool that back in 2009 we did not understand why this happened, but now we do. This is an example of a columbic explosion. A common misconception is that it is a result of the rapid production of steam, however if you try it with a non conductive substance like molten glass you don't get the explosion, only a conductive substance will work.
if ISIS ever gets to Canada.. were all screwed lol
No worries, Donald Trump's Coal Plant per Household Bill will fix that.
by Isis you mean the people the pentagon hire right?
Canada's current leader loves ISIS though.
I think it's magic
on rly the reaction its simple ... some fire extinguishers use water ... in a fire of class D (special class) its some metals can explode in reaction with H2O ... the thermite enter in this class D ( you NEVER can user water on thermite ) because the temperature its too hight to divide Hidrogen and the oxygen ... transforming it on a very very very powerfull feed for the reaction of the fire .... thermite on ice its the same thing ... the ... it cause the explosion ... shadered H2O transform in atoms of Hidrogen and Pure Oxigen ! cause a very powerfull explosion when ignited ! ^^ (im tecnic in work security) ^^
"It's a mystery - we don't know"
Oh my gaaaawd just CALL a university and ask for a physicist. You can't just leave things "unknown". If you don't know get someone who does.
*Chemist
TheKingOfChem Chemistry is just applied Physics.
KhazWolf Yes, But as a chemist myself my application for physics is little to none as a physicist does not use/know chemistry as well as I. That is why it is 2 separate jobs and why both occupations focus on different things
"Chemistry is the Central Science"
TheKingOfChem xkcd.com/435/
KhazWolf You're so stupid! What was the point of that picture. There is a reason why a physicist is called a physicist and a chemist is called a chemist. Anyways that website was about sarcasm. As a chemist in academia I think I know this better than you.
It's called a Phreatic Eruption or Phreatic Explosion, it happens in volcanoes all the time. The thermite is burning at approximately 2,200 degrees Celsius (around 4,000 Fahrenheit.) It's so hot that the ice directly under the bucket (because the thermite burned downward through the bucket and only came in contact with that ice) instantly turns to super-heated steam, and creates a steam explosion which is what shot the rest of the ice fragments everywhere.
Doesn’t explain why it explodes with ice and not water. You can drop thermite in water and it will continue to burn creating lots of bubbles but no explosion, I’ve seen it.
@@brett7406 This is just a guess, like they say in the video no one knows for sure due to lack of studies. They're not even sure if this is a chemical or physical reaction (or both).
One thing I'm thinking about is that when you drop an ice cube into a glas of bioling water then it always cracks with a loud noise. Maybe that's a smaller reaction of this?
Not quite, when ice cracks in warm water it's due to the outer surface of the ice ice expanding faster than the inside. In fact, since no new substance is acutally formed, it's not even a chemical reaction.
Maxwell Hebbourn
I see
Well look at the thermite wich is 3 times hotter than molten lava as the boiling water but it's doing this from the inside.I'm a pyromaniac trust me.
Being a pyrotechnician, would you consider aerosolized thermite a likely cause of the explosion in the video?
Oh yeah
They should've asked the ex FBI agent about the thermite used in 911
Fortunately Adam and Jamie are smarter than that.
A Hucal Yea true i looked into it a bit, apparently their not even allowed to talk about it lol
I think you may have misunderstood my meaning...
what thermite was used in 911?
Pianoguy32 No1 knows for sure but the current theory is nano-thermite. Thermite residue was found throughout the wreckage at the bottom of the tower and you can see quite clearly on the videos white smoke come out just before it collapsed but if it was smoke from a fire it would have been black due to lack of oxygen
2019?
Yup
Ever drop an ice cube into a deep fryer?
Yep, that's basically what happened.
No, never.
sirdavallen3 Dont...
James Goodall Didn't plan on it.
We were taught about, but not allowed to try, this on the Norwegian oil rig safety training back in the 80s. We were warned never to use water to put out a burning metal fire as exactly this would happen.
Basically the burning metal of the bucket will be so hungry for oxygen that it will split the water leaving hydrogen which builds up until it explodes. That's where the bucket went, it simply burned away.
It's a little like oxy-acetyline cutting. Once you have the steel burning you can apply pure oxygen and it will go much faster.
The center was hottest, created enough heat for the center to separate the two gases, building enough pressure to crack the outside shell. But that would have to go through the top shell somehow, unless it happened too fast for us to see it melt the top off quickly enough, it drops in, and the outside shell cracks.
To this day, I still don't understand why they went to a former FBI agent for explosives, and not an ATF one. Since the ATF's real acronym is BATFE and the E is for explosives...
My guess is something along the lines of a grease explosion. Dump grease into boiling water, it ignites, causing the water tonturn to steam, carrying greas particles with it, the now superheated grease is exposex to much more oxygen and explodes rather than a simple ignition. Same thing's happening to the thermite. Some of it's getting tossed around out of the fire, some of the ice is sublimating directly to steam, picking up particles of thermite, at the same time, the fire is melting through the bucket, alongside a steam buildup underneath, leading to both explosive decompression, and a dust explosion fueled by thermite. Which explains the two simultaneous explosions seen on the temperature view.
I agree but with the following added, the vapor is within the ice and the gas expands until it's container (the outer wall of ice) can no longer hold and the ice explodes.
Wait a minute...is everyone on TH-cam suddenly an expert scientist now?
The vapour isn't in a sealed container, so it can't build up the pressure on its own. However, the rapidly expanding vapour can scatter the thermite powder, as soon as the bucket fails, thermite goes everywhere, allowing it to mis with air faster, and thus burn faster, and there's the boom.
frank looks like a videogame npc when he says "iffy"
Yes, water vapor is not explosive by itself, but the heat converts ice into water vapor in a couple of milliseconds. Water vapor occupies a VERY LARGE volume compared to ice. This sudden expansion is the cause of the explosion (just like when a bomb goes off).
Miss this show so much 😢
It comes down to this it’s a high-pressure steam explosion, depending on how evenly the thermite pours over the ice depends on how powerful the explosion is
The "dancing ice cube on a griddle" experiment would confirm that theory.
It's simple hot and cold liquids. Thermite burns at over 4500F. With enough of it that's hot enough to turn ice to steam in microseconds = explosion. You get a similar effect taking a glass of water and pouring it in a 100-ton kettle of 3000F molten steel or other metal (bad idea, molten metal will fly everywhere just like in the video). Also happens when hot lava hits the ocean in Hawaii. They really should take a 100,000 fps video of this so the thermite touching the ice and melting it and watching the resulting steam blow apart the remaining ice and bricks and turning them into projectiles can be easily seen.
This is a scaled up version of an ice cube exploding in a glass of warm liquid.
***** You're not incorrect, however, that will cause burning, not an outward explosion. The water reaches its triple point well below the temperature of thermite at STP.
To challenge what you're thinking, check out the volume difference of steam and ice. Very likely this was a pressure explosion with some slight burning from the hydrolysis. The explosion was physical reaction, not a chemical.
***** Not necessarily, super heated steam has no "vapor" to speak of, its perfectly clear. it's entirely possible by the time it condensed it was spread out enough to not see any steam cloud.
A physicist and an engineer debating an explosion... It IS a friday night for me, so I'll get back to this tomorrow.
Awesome 👍
The slightly heated thermite at the bottom of the bucket condenses due to the cold ice underneath. When the flame finally reaches the condensed thermitet the thermite expands rapidly and EXPLODES.
thermite reaction is at a very high temperature, it creates liquid iron (iron oxide is a main component in thermite) molten iron melts aluminium bucket bottom, melts though ice creating steam, the deeper it goes - the more ice is turned into steam (lidenfrost effect) and more steam there is = more pressure built up in the cavity in the ice. hence the explosion...
en.wikipedia.org/wiki/Steam_explosion
Metal fires are usually left alone by firefighting teams unless absolutely necessary. In those cases, dry sand is used to create a barrier between the fire and atmospheric water vapor to prevent a steam explosion. Vitrified sand (glass) on a fire is safer than having it explode and then rain burning metal over a large area.
I get it.
Just can't get the talking walrus
Steam won't do a thing, because it won't have the pressure. Look at how slowly the ice melts. You can calculate the amount of steam generated. Since it's not in a confined space, it wouldn't build much pressure, certainly not enough to produce such a boom. Meanwhile the temperature of the burning thermite is far than enough to split water molecules, which produce oxyhydrogen, a volatile gas which can explode even unconfined. Also, more oxygen will not make thermite burn faster or explode.
It's the rapid expansion of steam from the ice. The thermite gives the ice so much energy it immediately vaporizes, causing an explosion so long as it remains in contact with the ice. Which, of course, is why it was so short and the ice was blown away preventing it to become any bigger.
The FBI Consultant could easily pose for Judge Dredd with that Epic Frown.
Maybe it's like how glass reacts with fire how it shatters all over the place.
yes I know. normally the Leidenfrost effect is done on a hot plate with a cold vaporiseble drop but here its the other way round. your theory could work if it was a solid block of ice and even then the flower pot would need a perfect seal and weigh several hundred pound. that lot can't way more than 4 so the pressure need to knock the bucket of would be quite low.
of course it exploded, you're super heating the ice in a couple of seconds, going straight from solid to gas without passing through the liquid state
If you're turning ice into steam over a few Seconds then it won't go boom. It has to be in a few milliseconds if not microseconds to get that kind of reaction only from the ice. Most likely the explosive power came from the thermite
Anju Maaka nope, except the time span ascdren is right.. at an atmospheric pressure of 1bar water freezes at zero centigrade and boils at 100 centigrade.. A thermite reaction has well over 2000 centigrade.. so you have to overcome 100 with 2000+ celsius.. i'm confident thats instant explosion..
clrscr
furthermore, the volume increase from ice to gas at 1bar is roughly times 1600.. so you dont even need much water to make a pretty big bang..
It is great how they did not expect the thing to explode. They always do the blast screen, but when they expect a real explosion they do the bunker. And the camera would not stand around but would be a remote controlled one…..
Thermite works via a transfer of oxygen between metals, normally iron oxide + aluminum to aluminum oxide and molten iron. Normally an aerosol of flammable materials is more explosive, but this is because it needs the oxygen from the air for the reaction. This is not the case for thermite reaction.
The reaction is readily explained with basic chemistry. What is happening is that the aluminum powder is reacting with the steam. 2Al + 3H2O -> Al2O3 + 3H2. This by itself would not cause the explosion but the hydrogen produced is mixed with the oxygen in the atmosphere and ignited by the thermite. The effect would be even stronger if the ratio of Aluminum powder was greatly increased in the thermite mix.
It is a textbook flash steam explosion, the thermite burns hot enough that it skips over the liquid state of water causing the solid to expand directly into a gas
Still don't get tired watching this one. Everyone was surprised that the myth actually worked.
Definitely a "Don't try this at home".!!!
I assumed is was like what happens when you pour hot water into a cold glass dish, it cracks or explodes. Since cold tends to condense molecules and heat expands, I assume that the rapid super heating is expanding the ice so quickly that it acts like a pipe-b, which is to say that it acts under intense pressure from the rapid expansion and shoots the fragments everywhere.
when the flame front hits the colder thermite, the force of the already burning warmer thermite escaping from the top of the tin bucket pushes down on the remaining thermite compressing the air, moisture and thermite. once the cooler thermite ignites it burnes far more ferociously due to the containment/pressure and also due to being enriched with oxygen as it cooled (cool=vacuum etc). just like containing other flamables and igniting them makes them explosive, this enriched slightly (MORE)