Poor man's "Liquid Nitrogen"
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- Опубликовано: 13 сен 2024
- UNSAFE, NOT FOR KIDS! Main article: bit.ly/TNXQ7
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Can't get liquid nitrogen? Then make your own -80C/110F fake version by using Dry Ice. Note that this science demonstration involves several major safety hazards, and should only be performed by skilled educators. If used for science fair projects, close parent/teacher supervision is required.
But also go see bit.ly/EKqgi SFGATE: "The War On Curiosity" (stamping out hobbyist science in order to keep kids safe.)
For lots of suggested low-temp physics demonstrations click on the above liquid_N2 link. Or, search www for: liquid nitrogen demonstrations.
Note that dry ice comes from companies listed in your local yellow pages. Some welder-supply stores carry it. In Seattle, you can find it in the seafood section of QFC neighborhood grocery, and at some Fred Meyer stores. Ask for dry ice pellets rather than slabs if they have them, so you won't have to chop it up yourself.
And if you're going to use it in drinks or punchbowls, make certain you have FOOD GRADE DRY ICE, since the other stuff is full of grease from petroleum distillation.
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Lots more stuff at SCIENCE HOBBYIST amasci.com/unew...
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Note: trolls/spammers blocked immediately, zero tolerance
After experimenting with this stuff for quite a while I found the risk of frostbite from splashes to not be too bad. The alcohol being as light of a liquid as it is clearly doesn't transfer heat as quickly as a denser liquid like water. I did dip a finger in quickly and what stuck to it was room temp just about instantly. So, there is a little bit of forgiveness for a mistake so long as you don't dangle an appendage in there for a second or more.
It's the number of moles per liter that matters, small atoms have an higher heat capacity because there are more atoms.
Water has a good heat capacity because it has two very small hydrogen atoms that can vibrate.
What I found to be the bigger danger was coming back to the experiment the next day and mindlessly dropping more dry ice into the room temp alcohol, which of course boiled over and went everywhere.
Cryogenic napalm would make a good band name.
@rockman999129 right below the LIKE button: main article about this. Or click on "Show more" for all that info.
@Robkat3751 No acetone. Rubbing alcohol.
I didn't mention acetone in the video, since it's a big spill/fire/fumes hazard if used in gradeschool classrooms.
For higher grades, just go get a dewar and use some real Liquid Nitrogen.
next video to watch: How to make Homemade Dry Ice
Grant Thompson did a video on how to make it
I will surprise my girlfriend for the very first time because my dingle will be so hard after I put it in that mixture.
Won't matter in the hospital
Grant Thompson should try Everclear 190 proof. Still may freeze your stomach lining, send you to the hospital. Make semi-lethal dippin' dots?
Nice suggestion Bill ;) I've actually thought about using that, but never got around to buying any yet. Sounds like a future experiment?!
It's awesome to see this account still active. I remember when these types of science videos weren't very common on RUclips- wbeaty was definitely a pioneer. Like I said good to see activity!
Grant Thompson - "The King of Random"
Haven't tried that yet. In WA state it's not legal, must get it elsewhere (only 151 proof sold here, 75% thick like paste!) Other states list: en.wikipedia.org/wiki/Everclear_%28alcohol%29
Grant Thompson - "The King of Random"
also DRY ICE SAFETY WARNING: if not "food grade," it's usually from an oil refinery and has trace amt ?acetone benzene? etc., Makes things greasy. Fire-extinguisher dry ice, is it always food-grade type? It may be like popskull moonshine, cause headache and nausea if mixed with food.
wbeaty My dumb ass years ago bought 5 pounds dry ice for a party on Friday. I bought it on Monday and when I opened the paper bag to get it out I said " We've been robbed". I googled it and discovered I was a moron and I know better now. You would be surprised how many people do that.
@guitarmaniac927 Nope, see my other videos. You can also stick your hand briefly in liquid nitrogen, or roll some droplets of LN2 around on your palm. THe Leidenfrost effect protects you. But don't grab dry ice and squeeze. That really stings, doncha hate it when that happens?
Ahhhh I remember this video! I used to watch your videos a lot to ease my anxiety. I think you're one of the reasons I got interested in making science videos. I'm glad to see your channel is still up.
Thinking of this for some cooking experiments---would replace the rubbing alcohol with Bourbon or such!
Just make sure to get "food grade" dry ice.
The industrial grade dry ice comes from oil refineries and is full of nasty stuff, gives headaches and nausea.
Also, if you make high-proof alcohol slush using dry ice, it will destroy your stomach and esophagus. Cryogenic Napalm? Occasionally they make some in taverns by accident, then it's in all the news headlines.
Grant thompson king of random sent me!! Great vid!
Damn rip grant
Grant Thompson sent me!
It's just like learning to use a stove, or to work with high voltage. First, be terrified of getting burned/zapped. Then do it anyway. We'll try like hell to detect/avoid all possible hazards. We'll read up on it, we'll convince an experienced user to help out. And if we do get a major owie, we'll take responsibility, and not pretend that someone else is really to blame.
Chemist here - we use dry ice/isopropanol or dry ice/acetone baths all the time. Dry ice/acetone will give you a temperature of -78 Celsius, which works for most applications. As you've said, it's worse to touch than liquid nitrogen, since it sticks to your fingers. Also, you can't pour it into a different container - the dry ice carbonates the solvent, and warming it up causes the CO2 to bubble out like a soda going flat. It doesn't condense liquid oxygen, though, which is good. LN2 does.
@abbymichellexx see my other video DRY ICE IS IT LETHALLY DANGEROUS? Dry ice behaves like hot baked rolls or pizza crust, won't burn you instantly. No problem if touched briefly under 2sec, or juggle it between hands. But if you grab and squeeze, gives you bad frostbite blisters.
See my other video DRY ICE LETHALLY DANGEROUS?
Handling dry ice is like grabbing extremely hot pizza crust, or buns from an oven. The stuff is a poor heat-conductor, so you'll be OK if you just keep it moving (juggle it between hands.) Just don't touch the alcohol. Cryo-alcohol is a GOOD heat conductor, so it's like touching some sizzling bacon grease, or hot pizza cheese.
@science127 See my other dry-ice video. Is dry ice lethally dangerous? Nope, but it's not totally safe either. Kids shouldn't touch it until they've learned how to handle it without getting stung. The main hazard is from bursting of sealed containers. Also it's a very bad idea to sit inside a hot car with paper bags full of dry ice and all the windows rolled up.
@stripesthebird go see my other video where I intentionally freeze my hand, then chew up a Dry Ice pellet..
Anyway, I think you're missing the point. Similar to frying some eggs on the stove, dry ice is dangerous for little kids. It's like cigarette lighters and sharp knives and power tools: it's possible to hurt yourself if you're too young or too ignorant. Example: if you often cut yourself with butcher knives, it means you should stay away from them, since don't know how to use them.
For dry ice, check your local online telephone book. Or, call nearby large grocery stores, and if they don't sell it, ask them if they know which stores have it. Here in Seattle the welders-gas supply shops sell dry ice. Sometimes even gasoline stations sell it during hot season.
> we have google and ebay
***** Yeah, WE do. What small percentage of the world is that? When answering questions on youtube, don't mindlessly assume they're only from rich white Americans.
The questioner couldn't find dry ice, and also was non english speaking. If goog search for local groceries worked in their country, they wouldn't have to ask.
Ethanol (from Lowes or Home Depot) works well too, and has a lower melting point (-114C) and opposed to -89C for isoPropanol, but both are below the temp of dry ice (-78C). It is more dangerous than liquid nitrogen as there is no liedenfrost effect since the alcohol doesn't boil below skin temperature. This technique is also a "poor man's" way to recover the freon from an AC without having an expensive pump. Evac a tank, hook up to AC, submerge tank into dry ice and alcohol bath.
Depends on large sink, small ice cake, & drafts in room. To verify, put hot water on dry ice, and the pure CO2 pool is the white part w/water droplets fog. If drafts are carrying the CO2 away, you can verify this happening if the CO2 is visible white.
Yep, also it's CO2 snow without a flat surface, and also it forms an insulating gas layer when touched to warmer surfaces.
Dry Ice does not instantly burn you (freezer style), I have held some it is cold as the arctic in your hand but not cold enough that touching it will give you frostbite. It will however do this by HOLDING it bare handed and even then it takes a bit longer than you'd think.
I've done it too. It only stings a bit if you don't leave it in your hand for a long time. My friend once left it for longer and hand all white, and he said that it hurt like hell when melting back to normal.
The reason it was squeeling on that video which im sure youve watched is because they were applying pressure to the dry ice therefore the cutting would release the condensed pockets, creating a noise.
@baseballboy0101 Go see my other vid: "Dry ice, is it LETHALLY DANGEROUS?
What is happening is the alcohol is acting as a cold sink. Since alcohol has a very low freezing point it can "abosrb" much of the cold from the dry ice and stay a liquid. Now that the alcohol is very cold, it can freeze objects quickly due to the high surface area of the liquid. Acetone works well for this also. Different solvents will give lower temperatures than others.
@ManuelHung Oh, and if you're only trying to make regular ice last longer, (no alcohol was involved!) then yes, there are much better containers than coolers or styrofoam. Ice lasts longer if drained, if no water builds up and connects to the container walls. Professional dewars for liquified gases use "superinsulation" made from a vacuum chamber filled with layers of aluminized plastic film (mylar space-blanket!) No vacuum needed, add a styrofoam layer to the inside, wrap with silver mylar.
Watched this as a kid love science still
Adults have no trouble using knives. (Dry ice isn't for kids in the first place!)
But go try the hammer. Dry ice is compressed CO2 snow, and hammers tend to either make huge chunks, or lots of powder. If you want chips, a knife works well. Icepick doesn't work. Easiest: buy dry ice pellets instead of slabs or blocks. Usually a welders' supply shop carries both.
@SnapleLover It's much like hot pizza crust: it will burn you if you grab and squeeze. But if you keep juggling it back and forth, you can carry it around. Chilled alcohol at -85C bites instantly, while dry ice takes a couple of seconds because of the gas layer.
At high pressure it's like water, it boils or condenses.
If you go a mile deep in the ocean, you can uncork a CO2 fire extinquisher and pour the liquid CO2 out in a puddle. It's a bit heavier than water.
Go find: PHYSVIDS video archive. On page 15 there's an ROV sub with cameras near a blacksmoker volcanic vent, with liquid co2 globs rising out of it. They call it the Champagne Vent.
It's still just alcohol. But carbonated.
Let it warm up and fizz before putting it back in bottle, else bottle might inflate and pop.
I label my bottles, since it tends to be contaminated by shattered flower petals etc.
@k2rider69 exactly. Dry ice is obviously a poor thermal conductor. You can touch hot coals, but hot grease gives you serious burns instantly, even though hot grease isn't glowing red.
This is the first you tube science channel I ever watched. Loved these back in 08.
@PurpleSceneKidd it gives fast frostbite like liquid Nitrogen. But LN2 is colder, so LN2 freezes flesh more quickly. On the other hand, warm skin creates an insulating gas layer with both Dry Ice and LN2. This slows down the frostbite effect.
Liquid alcohol at -90C is less safe, since there is no Leidenfrost gas layer, so it gives frostbite almost instantly.
> is like 20 dollars a gallon
Cheaper than that. But you need a storage dewar, buy (expensive) or rent one from supplier.
A thermos is too small, it will boil away before you can use it. And most places won't deal with non-professionals who lack proper containers.
If you dump wattage into it, it heats up fast, basically same as normal ice. Dry ice gets you low temperature, not high cooling
I once made that experience. For some reasons I put dry ice in a sink and bowed my head over it, relatively deep into the sink. I could inhale without pain but didn't gain any oxygen. I just could put my head out of the sink... CO2 is heavier than air and gathers at the bottom of the sink if dry ice is evaporating.
A few lbs of dry ice in a styrofoam box will last for about a day. To go longer, wrap it in many layers of silver mylar sheet, put it in a styrofoam box with a lid, then put that in a larger styrofoam box or beer-cooler.
Click "show more" to view text explanation.
Same as dry ice, or perhaps slightly below. -110F deg
Interesting... This is essentially what we use in a chemistry lab to cool a rotary evaporator, or "rotovap". There's a large chamber that can be sealed to create a vacuum, and the vacuum chamber is kept cool with an inner tube filled with 2-propanol and chunks of dry ice. It's a fascinating device, when you think about the physics of what's going on there.
@PACIFICFL0W better watch all my other vids. Dry ice, is it LETHALLY DANGEROUS?
This is a great little video- I like your sense of humor. "Don't put it in your mouth" "It's like cryogenic napalm"... Awesome.
Liquid nitrogen is at -210 degrees Celsius or 63 kelvin. Dry ice is carbon dioxide and is a solid at about -80 degrees Celsius or about 200 kelvin, as you have stated. The only thing you have done is cooled alcohol which has a much higher heat capacity and will therefore freeze things fast, but only to 200 kelvin. If you are a science teacher you will have easy access to Polyethylene Glycol, much higher heat capacity, much quicker freeze.
I don't know. But adding the cost of all the dry ice, it's probably cheaper to buy un-denatured ethanol. Try freezing out the water, you could make applejack Applejack, or Brandy^2
Could the difference between quantum and classical physics be because quantum physics represents the passage of time itself?
This theory is based on just two postulates,
1. The first is that the quantum wave particle function explained by Schrödinger’s wave equation represents the forward passage of time or Arrow of Time photon by photon
2. The second is that Heisenberg’s Uncertainty Principle that is formed by the wave function is the same uncertainty we have with any future event.
I've been using mineral spirits solvent and dry ice as my poor man's liquid nitrogen to shrink press fit parts and bearing for years
"it's like cryogenic napalm"... as he does the whole damn thing without gloves on. That's ****ing brilliant!
You can do that, just don't let it stay in one spot on your hand for too long. As long as you keep it moving it won't hurt you.
Yes, but only down to the temp of dry ice, -110F.
Liquid nitrogen is -320F. But in many cases the alcohol cools objects faster, because the liquid nitrogen has an insulating gas layer during boiling.
LN2 needs a license and dewar. Same with Dry ice. The coldest you can have is in a freezer, at a temperature of -40 degrees Celsius.
Try it. Flame goes out. It's full of CO2. Also, in order to burst into flame, alcohol temperature needs to be above 32F, the "flash point"
freezing point of isopropyl alcohol -128.2 F freezing point of dry ice -109.3 F
Wouldn't acetone be a better choice? For sub-freezing cold baths in lab settings we use chilled acetone rather than alcohol. It doesn't become more viscous at those temperatures.
@1770studios Liquid nitrogen is much colder. Liquid nitrogen boils, so it creates an insulating gas layer if you touch it.
@1112Hades Right. Dry ice is -109 F and liquid nitrogen boils at -320 F. That's a big difference. But with the price of dewars and liquid nitrogen, not many people will buy it. I think his point is regardless of temperature difference of the two, the ice is a poor thermal conductor so super cooling alcohol creates a similar effect of liquid nitro.
@MrDaverulz might work better than LN2. LN2 is colder, but it boils and leaves an insulating gas layer against the metal.
> still flammable
Nope, it has to be warmer than 0C. Look up flash point. However, even chilled alcohol will burn if a wick is provided. Same with candle wax, veg oil, etc.
@Mr3wheeledbike plastic pumps and plastic hoses become brittle. They may shatter. Also don't mess with LARGE amounts of dry ice. Large amounts of dry ice aren't safe ( because of suffocation danger.)
Object-launcher: vacuum pipe with foil on both ends. Frozen cherry inside at one end, break that end's foil. Cherry exits other end at ~1000ft/sec? How deep through clay block, or into wood?
99% rubbing alcohol can be hard to find. An alternative that might work would be Everclear grain alcohol.
I could have used a little of this last time I was replacing the valve guides in my Suzuki 1100.... shrink the guide,stove heat the head, gently press fit.
Dispose of rubbing alcohol? Put it back in the bottle, label it as USED FOR DRY ICE BATH. Note that it's now effervescent, so don't put the cap on very tight.
Acetone? Doesn't mix with grade school children! This video is for school teachers and students. Everyone else just goes and grabs some liters of LN2 from the stockroom dewar.
Never actually worked with dry ice?
It acts much like hot pizza crust. Keep dry ice moving in your hands, and nothing happens. Grab it and squeeze, and YEOW! It's not for little kids, but adults quickly realize that gloves aren't a strict requirement.
Go see other vid about chewing dry ice then spewing fog out your mouth like a CO2 extinguisher:
Dry Ice: is it LETHALLY DANGEROUS?
youtu.be / c3B5I4rpMrs
Actually, the alcohol isn't supercooled. %99 isopropyl alcohol freezes at -88°C, while dry ice only reaches a temperature of -78.5°C. To be supercooled, the alcohol would need to be cooled below its freezing point without solidifying.
@wbeaty alternative method for freezing the daisy
Warning: FIRE HAZARD
get a refill buthane tube/canister, best to use is the spray can type for refilling buthane lighters.
turn upside down and press open the valve to let the liquid buthane escape into a insulated container. optional, place the refill in the freezer before letting the buthane out, it increases the yield of liquid buthane.
now you have a luquid gas that should be able to chill things down to -40 deg centigrade.
The 2-bottles chamber maintains constant temp for ages (just keep adding more CO2.) For demos at outdoor fairs, a long line of kids each get to freeze a flower.
Even pliers won't break the cherry. Mythbusters should carve frozen cherries into rifle bullets. I think I re-discovered PYKECRETE, the waterice composite material which supposedly shrugs off Nazi torpedoes, but a-bomb made pykecrete battleships obsolete. Why hypervelocity orbital weapons using frozen pineapples? Why not?
For all of the peeps saying its not safe I could understand if little jimmy or Sally gets hurt but he is doing his passion like me playing a sport safely because I care and he even says not for kids
@reddog418 Touching alcohol at -85C causes pain in a fraction of a second. Touching liquid nitrogen or dry ice does not; not for many seconds. Leidenfrost effect involves gas, not water. Dry ice will spew out a gas layer and float above a tabletop, no water needed. So will liquid nitrogen droplets. (Play "air hockey" with dry ice chips, like little hovercrafts.)
Dry ice is like hot bread. You'll get burned if you grab it and squeeze. So just keep it moving in your hands.
Gloves are definitely needed for carrying large chunks.
Frostbite is almost exactly like a heat burn because it kills flesh. It gives painful destroyed skin, then large blisters.
to make dry ice use a CO2 fog horn fire extinguisher and fill up things like pillow cases.
> make ice cream with this stuff without dying?
Not rubbing alcohol! And use food-grade dry ice, not the toxic oily industrial type. Maybe try 151-proof rum, and icecream mixture pre-chilled in the fridge. Or instant frozen margaritas? In some states 190-proof Everclear is legal (not WA though.)
probably. But the further from 100%, the thicker it gets. 99% rubbing alcohol is cheap, while 200 proof ethanol is expensive and even illegal in many USA states.
I noticed a difference liquid nitrogen seems to be able to shatter objects after they are thrown and fake liquid nitrogen seems to just make the objects solid instead of shattering type solid
yeah let me just grab my emergency space blanket real quick
> acetone
VERY unsafe for grade school science. Also, it's not available in neighborhood grocery stores as is the 99% IPA and dry ice.
Chem labs do usually use acetone+dry-ice when liquid nitrogen is too much trouble (boils away too fast.)
Yeah, it gets carbonated. Then it's like putting ice cream in warm rootbeer.
Also, plastic alcohol bottles aren't built to take fizz pressure. If the "used" alcohol is stored in the original bottle, better shake it up and vent the pressure. Otherwise the bottle might swell up and pop.
@OnnomonnomonnO Just go try it yourself with dry ice. It doesn't really matter how hard you hit them, a frozen flower shatters when struck. Also, the petals break if you try to bend them. Same with leaves.
This strikes me as significantly more dangerous than liquid nitrogen, due to the evaporation of a highly flammable liquid.
Further, the cooled alcohol carriers a higher risk of cold injury to unprotected skin as nitrogen flash boils on spot contact and creates an insulating barrier of gas. The alcohol doesn't do this, and will remain in contact with the skin having a greater cooling effect.
Yes, it was a large and deep sink, and there was no drought in the room so the CO2 could make a "pond" for a certain time span.
Yup. My Dad used to bring home dry ice from his butcher shop for me and my brother to play with when we were kids. We would play hot potato with it.
i love you man, a true breath of fresh air on youtube, i hope you find something to make the ''poor man'' live forever..
@baseballboy0101 go see my other vid. I chew up hunks of dry ice. Spit out fog jets.
Probably: drip some ice-cream mix into the cryo-alcohol. "Dippin' Dots!" But wetted with rubbing alcohol? Instead use 190-proof Everclear(tm) ethanol (which isn't legal in many USA states.)
Also, adult alcoholic frozen drinks? More like instant smoothies than like ice cream. Chill some vodka with dry-ice chunks, then pour it into pre-cooled mixed drink and stir. Frozen margaritas AND CARBONATED.
my god the "water in a bucket over the door" just got cryogenic.
Electrical Engineer, U. of Washington, past head of sci. museum tech dept MOS, grade school textbook consulting, etc.
I did once teach HS physics at a private school
@inJCwepray Different meaning of Denatured. He's talking about "denatured ethanol" with added mild poison to prevent human consumption.
I know a story about this. Chem students used a still to remove a laxative substance from denatured alcohol. Instead, the still concentrated it. With expected results. :)
At school we harvested many gallons of used beer from cups at the end of parties. Distilled it. Discovered an amazing perfume: Beer Party Sticky Floor! Charcoal filters removed the stench
To be honest, I was skeptical at first, but this is actually pretty clever. The fact it's not a condensed gas, though, does make it a bit dangerous, and I'm not sure how much money it actually saves. I thought the price/volume was pretty low for both of these. Is dry ice that much cheaper than LN by volume, or is it just harder to get small quantities of LN?
@wizzofwater101 alcohol has an insanely low freezing point. So the dry ice makes the alcohol almost as cold as liquid nitrogen. Using standard water, the water will merely freeze solid.
When you said "cryogenic napalm",my mind exploded with ideas :D
@kackiz You can use LN2 to condense out some LOX. First make liquid nitrogen. Put it in a metal cup or pipe. Liquid oxygen drips off the outside.
But probably you'd have to dry the air somehow, since frost builds up faster than the liquid oxygen.
It will only hurt you if you hold it too long, squeeze it, or are holding a relatively large chunk.
@wbeaty actually...sublimation protects your hands for 6 seconds until tissue damage occurs
> use gloves
Kids need to use gloves with dry ice, and possibly heavy clothing and a face shield. Adults can figure out the level of danger. Small hunks of dry ice are about as dangerous as hot pizza crust. Just don't grab and squeeze hard. Carrying a 2KG chunk around? Yes, then gloves would be wise.
Being terrified of dry ice is like being terrified of lawnmowers, hot stoves, and carving knives: quite dangerous for kids, but adults figure out how to avoid pain/injury.
Have you looked up the formula for "true" napalm? They stopped using it and moved to Napalm B. Want to guess the composition? Add some additional benzine to your above listed formula. Instead of burning for a few seconds to maybe a couple minutes, it went to 10 min+. Cheaper too.
I saw the quantum levitation video, which uses liquid nitrogen and a magnet to levitate the magnet.
I was curious to see if there was applicability of such things for transportation and supply chain systems. But, we already have magnetically levitating train tracks in China, Japan and some of the other countries. I believe the existing tracks work by quickly alternating the current on the two sides. When the electro-magnets have their polarity switched that quickly, they end up propelling each other. I could be wrong!