Added: 3 years ago
From: aaronakeller
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  • You're a great teacher.

  • V/T=c iff pressure is constant.

  • I love school. They say it's not a toy and then show you a bunch of fun stuff you can do with the thing that's dangerous.

  • lol, 'can i have half'?

  • I thought you could touch for like 2-3 seconds due to liedenfrost effect. The heat of you hand causes a gas to form "levitating" the drops of liquid nitrogen.

  • @DomR1997 See my comments below about the Leidenfrost effect. Also, see my video response to this video which demonstrates it for water on a hot-plate and for liquid nitrogen.

  • This is WHITCH CRAFT

  • Why have my chemistry lessons always been boring...

  • @adidastwist69 you can get frost bite from touching it and that usually results in the frost bitten part of your body falling off.

  • @yippy010 Not necessarily. Scroll down through my comments and take a look at my Leidenfrost Effect video for further discussion.

  • @yippy010 leidenfrost effect is what happens when you drop water onto a screaming hot stove and it moves around theres a layer of steam protecting the water from boiling instantly

  • So in the movie Terminator 2 when the bad guy at the end freezes on the spilled liquid nitrogen and his legs and arms starr breaking, can that happen in real life???

  • @adidastwist69 Not really. Frozen flesh of a person (which Terminator 2 was not) is mostly frozen water. It would be about as fragile as a big block of ice. The flower breaks easily because it is thin.

  • R.I.P Lilly flower :(

  • Shouldn't the nitrogen be very cold when it gets on your skin after it boils back into a gas?

  • You could use liquid nitrogen to huge forest fires? This would stop the fire immediately.

  • I would def have enjoyed this class

  • Is the fog condensed water vapor?

  • @runerman17 Exactly right. I even have another video about exactly that phenomenon of the fog created in the air from water vapor by the cold evaporated nitrogen gas.

  • Now to make nitrogen ice, would it need to be at lets say -500 F?

  • i wish i had a teacher like him

  • 3:35 "WHOAAA... Duuuuuude"

  • Good teacher!

  • very impressive Mr. Keller

  • @ 4:35 wouldn't it require an INCREASE in pressure to create solid nitrogen?

  • @pjwho "What I said is a bit misleading. The way liquid nitrogen is made is by compressing air (which heats it up) and then allowing it to quickly decompress. Some of the air escapes, taking heat with it. The cycle is repeated until it is cold enough to liquefy. Then by fractional distillation oxygen and argon can be separated. When I said 'reduce the pressure' this is what I was referring to. Of course you would also have to compress it but the hard part is getting it cold enough."

  • it wouldnt freeze ur hand instantly cuz of the leidenfrost effect right?

  • One thing i don't understand is why the liquid nitrogen should actually cause the candle to go out. While it is true that nitrogen has no oxygen, it is still cold. the air still has oxygen, so some oxygen should liquify and fall on the candle. Since liquid oxygen is a good oxidizing agent, the candle should keep burning. I hope u can understand what i mean.

  • @jhunkubabu The liquid nitrogen may collect some liquefied oxygen but I suspect the amount would be very small. When I put out the candle I am pouring cold gas that has evaporated from the surface of the liquid nitrogen. The liquid nitrogen really is 100% nitrogen. This gas will be (probably) at least 99% nitrogen because it will have completely displaced any regular air. I seem to recall reading somewhere that flames require more than 18 or 19% oxygen.

  • @jhunkubabu Whereas there will be a little bit of oxygen, the amount of nitrogen is far more abundant, to the point where the flame simply doesn't have enough oxygen to continue burning.

    Additionally, the extremely low temperature of the nitrogen saps the heat from the flame, meaning it couldn't burn even with the oxygen.

  • Great Presentation

  • i wish we could have any experiments at my school =/

  • What a fantastic teacher.... He makes science fun:)

  • I am studying A level biology and chemistry and found this very fast moving, fun, understandable and informative...thank you.

  • This got a lot of views for a science demonstration, but make more! This really interested me!

  • Would the university in my area maybe give my some?

  • Haha the man that laughs at 3:40 smh.

  • awesome!!! it really do help m a lot 4 my hw LOL!!!!!!! anyway thanks a lot!!!!!

  • Nice demonstration, but the class is asking stunningly stupid questions.

  • @TheAdmiralPancake That was stunningly unkind of you. Were you born knowing everything? Patience is required when teaching students and showing them something completely outside of their experience. I hope you are kinder in person than you are in semi-anonymous postings on YouTube.

  • @aaronakeller

    I'm sorry if my comment sounded rude. A stupid question isn't a question that is stupid. It's more like a joke question. The question "Can I have half?" would be a perfect example. It's not a serious question about the class. It's either unrelated to the class or is a joke.

    That's the meaning I was going by. By that definition, your class did ask stupid questions. I didn't mean to call your class stupid, just say that some comments were total non-sequiters.

  • @TheAdmiralPancake Fair enough. As a classroom teacher I just ignore that stuff!

  • wow he knows what he is talking about!!!!!

  • Fun With Liquid Nitrogen - Cool Science Experiment

    79% of air is nitrogen they claimed while here is 80%

  • @piemanrocksyea I said 80% because that's close enough in this context. How many significant figures do you need in your measurements?

  • @piemanrocksyea as far as i remember, he said ABOUT 80%... not exactly 80%... for me, 79% IS in fact ABOUT 80%

  • With the ledeinfrost effect you can put your hand in liquid nitrogen with no harm to you there is a gas barrier around your skin and as long as you do not sustain contact with the nitrogen you will be fine

  • @imak3ueat I posted a comment on the video about this and have even posted a reply to this video about the Leidenfrost effect.

  • Liquid Nitrogen is cool.

  • 3:36 for WOOW DEWD

  • lol "Can i have half"

  • If you where to put a human hand in it, would it turn black or would it freeze and give the same effect as the rubber ball ? As in, it would break if you hit it.

  • @TheRaevin As I understand it, no. Animal tissue of any kind is not susceptible to shattering upon being frozen solid. Try to shatter a frozen steak from the freezer and you'll see what I mean. The reason the rubber ball can be shattered is that is a single substance that has a glass transition temperature above the boiling point of liquid nitrogen. That means that when dunked for long enough in LN2 it becomes rigid and fragile.

  • @TheRaevin look for the Leidenfrost effect on google

  • Thanks for posting! Helped me understand a lot :P

  • This was neat Video..lots of good information

  • I want him to be my teacher!!! mazing class what scho0l is that?? great vid :)

  • Chemistry is awesome :)

  • nice class

  • Your teacher is Adam Savage :O

  • I could have been a good student if my teacher was this awesome and the class was this fucking badass

  • @aaronakeller, uhm as cold as it may be, when it touches a surface, like the floor, would an area of the surface somehow get hot?

  • @Nuan3677 No. Boiling liquids do not necessarily need to be 'hot'. The floor in this case is hot, in a relative sense, compared to the temperature of the liquid nitrogen. In an absolute sense, the floor is not hot. At least, it's not hot in a way that you or I would normally define it. After having the liquid nitrogen on it, the floor gets colder.

  • Science is AWESOME!

  • Lol 1:52 "Thump"

  • Can i have half?

  • Shouldn't you wear gloves when doing this kinda stuff? Even though it might not harm you?

  • i want one!

  • can i have half

  • he should've demonstrated some N cooking skills too

  • do you need a license to buy this?

  • @lvll138inrs Probably not. But be aware that if you don't already have some experience with it and know how to handle it safely you could be vulnerable to some terrifying consequences. Stored incorrectly liquid nitrogen can cause intense explosions, for example. You know how ads always have a disclaimer at the bottom when the person on screen is doing something incredibly dangerous? "Do not attempt."

  • @aaronakeller Can you buy this online? I really wanted to do a experiment with this but at my own home if its up to 50 or 60 dollors for maybe a gallon that'll be fine.

  • @mrhilov8 I have never tried to buy it myself. I have only ever used liquid nitrogen for demonstrations that I obtained through a university or college lab which normally stocks it.

  • @mrhilov8 liquid nitrogen is stocked at most welding supply stores and costs about the same as milk.

  • @mrhilov8 liquid nitrogen is sold at most welding supply stores and is about the same price as milk.

  • Chuck Norris drinks this!

  • Put on "CC" and look at 0:07 "I consistently have studios insist bunnies that night" Hahaha

  • liquid nitrogen is actually liquid essence of chuck norris

  • I'm being curius now,but,where did you found (or make) the liquid nitrogen?

  • @EpicTrollThatTrolls The liquid nitrogen I used in this video was supplied by the generous folks in the lab at Bowdoin College in Brunswick, ME. They had it delivered to them by a local gas supply company that also supplies 'refrigerated liquids' (as they are often called). Liquid nitrogen is made by liquefying air and boiling off the oxygen and other components in the atmosphere. To turn a gas into a liquid it must be cooled (a lot). To do this the processor usually allows it to expand rapidly.

  • @aaronakeller Thanks.I was just curius.:)

  • @aaronakeller do u mean the melbourne brunswick?

  • @Gasolinelitmatch15 Melbourne Brunswick? No, Brunswick, Maine, USA.

  • what property does this follow?

  • i have a question if you were to take something like a orange or apple and put it in liquid nitrogen for long periods of time would it have the same effect as a freeze drier and remove all the moisture from a object such as a apple, or orange

  • @23cecropia I've never tried it but here's what I think. It would just cause the water in the fruit to freeze solid. Cell membranes would break but probably not enough that much of the moisture inside would escape. So, I don't think you could freeze-dry by simply storing something in liquid nitrogen.

  • @aaronakeller

    I agree with this only partially.

    Freezing with liquid nitrogen is only a partial step in freeze drying. What you say is true, but what you do after is lowering pressure and increasing heat just enough for the water in the object to sublimate. Once you do that, the object has been freeze dried.

  • @formula90II Ahh. OK, if you decrease pressure and continuously evacuate the moisture as it sublimes, then yes, that would be freeze drying. I thought you meant to just dunk it in the liquid nitrogen. Which wouldn't work.

  • No, Liquid Nitrogen will not give you frost bite 'instantly'. You can pour it on your hand even dip your hand in it, for a short amount of time of course.

  • @DrewManDrew1992 about four months ago I commented: @WoRtH1milli You are correct, brief contact will not cause instant damage. I believe I posted a comment on the video about this... Is it not showing up on the screen at the appropriate time?

  • @aaronakeller no its coming up at the right time just some people want to criticize your video before they take a chance to look at the comment popping up in your video saying to go to the video response and stuff like that i love this video, a few days ago my chemistry teacher did a similar demo.

  • @QuickSilverize I appreciate your comment very much. Glad you like the video.

  • What would happen if you filled the balloons with helium? Would they float when they come out of the liquid nitrogen?

  • @DillonPiano They certainly would float when they came out of the liquid nitrogen. What an awesome idea!

  • T-1000 > Balloons.

  • oops i spilled it......

  • i wish i had that guy as a teacher.

  • How do I store liquid nitrogen?

    Can I just leave the dewar on room temperature? can I leave it inside my car?

    What happens when I didn't consume all of the liquid nitrogen?

  • @punchingpower Liquid nitrogen is stored in two types of containers. One is a large, pressurized gas bottle designed to handle and deliver gases in liquid form. These are vented to prevent explosions. The Dewar flask is a very well insulated thermos bottle. Liquid N2 stored in such a flask eventually evaporates away. I wouldn't leave it in your car since N2 displaces oxygen and you could make the air inside unbreathable. Whatever you don't use will evaporate so use it all up if you can!

  • This guy seems like a really good teacher. If my teachers had been more like this I would've done better in school.

  • Nice application of Charles' Law.

  • why would ppl dislike this video..

  • Liquid Nytrogen! It's Miracle!!!

  • Can Nitrogen be combust under any conditions?

  • @SailorSaturn69 No, nitrogen does not burn in air. Air is (as I say in the video) nearly 80% nitrogen so we should be glad it doesn't. There is an interesting reaction between magnesium metal and nitrogen that is something like burning but it requires a much higher temperature than you'd ever see in a candle flame.

  • that's lady's and gentlemen is how classes should be. unlike all of the classes I've been through

  • Awesome teacher! Wish my lecturers were more like this guy, instead they are boring fookers!

  • What if you put liquid nitrogen on an actual hot griddle....0.0

  • @TalkDaTech More of the same spattering, no doubt.

  • @aaronakeller would be awesome...

  • wow, with a teacher like you its almost guaranteed I wont flunk lol :)

  • 3:37 dude.....

  • Is this high school?

  • @lovemonkey217 Yes, but during a summer program held at a college with access to materials like liquid nitrogen.

  • I wonder what happens to Mercury if you put it in this Liquid Nitrogen or you know.. put Liq.N on the Mercury

  • @alitareqali I think Theodore Gray has a picture of a sculpture made of mercury frozen with liquid nitrogen on his site: theodoregray . com / PeriodicTable (on the page about mercury). I'm pretty sure the stuff just freezes solid and looks like any other metal.

  • I'm so looking forward to this class

  • jamie & adam hybrid?

  • what an awesome science class!

  • I wish our Chemistry department was this good. App State Chemistry kinda sucks.

  • coolest profesor EVER

  • Very Fantastic vision on science experience to show on! Awesome.

  • Comment removed

  • @JohnEdroid I am the teacher in the video. Click on my name and you'll see mostly videos of me doing chemistry demonstrations. (I think you might have mixed up who wrote each comment: my comments begin with @hitokiri657 because that's the person the reply is for).

  • @aaronakeller Sorry about that. I removed the the other post so as not to mislead others.

  • He's my 11th grade chemistry teacher. Hes freakin awesome.

  • @mee11mee he's gonna be my teacher next year if he still teaches AP. Should I be scared..? :p

  • @timisian Just be prepared for good quanitites in amounts of work, and take notttttesss.

  • @mee11mee Did you take AP? Cause i talked to some kids and they all told me not to take it, but I'm still going to anyway

  • @timisian no i didnt. just regular old chem

  • I liked the comment "Nitrogen has no oxygen in it" haha

  • clean your blackboard!

  • chem next year, i wonder what happens when you put methane gas inside with a flask of liquid nitrogen and light it on fire.... hmmmmm......

  • COLLEGE FTW! I'm taking chemistry in 9th grd. atm

  • damn where were you when i was growing up? my chemistry teacher sucked .she had no knowledge like this .well if i ever figure out time warp ill be at the front of the class ,keep up the good work

  • Thank you so much, Aaron ;). Been to a lot of help. Been wondering about this phenomenom for a long time, a lot more describing than Wikipedia ;)

    Chris

  • unlike the rest of you, i am made of liquid nitrogen.

    well cya, i have to get back to my planet now

    lol

  • You almost make me miss high school.............almost!  Great job

  • I'm not into chemistry but this was sure very interesting to watch the whole vid...wouldn't mind taking a few classes like these if a teacher was teaching just like were doing in this vid. :)

  • mythbusters look-alike

  • wish i hace had such a good teacher.....

  • If only my chemistry / fysics teachers had achieved such a hands-on approach to the classes I had... Great job!

  • I KNEW I've seen that lecture room before! (horrors from organic chemistry)

    Great demonstration :)

  • Liquid Nitrigen + Snake = SOLID SNAKE!! :D

  • thumbs up if you were bored and typed 'liquid nitrogen' =)

  • If teachers can be awesome like this and make chemistry interesting, you have my spot in your class.

  • "DUUUUUUDE" X 30

  • 2:52 that's what she said :)

  • @ ~4:35 Solid nitrogen requires an INCREASE not decrease in pressure... just in case ;)

  • @hitokiri657 What I said is a bit misleading. The way liquid nitrogen is made is by compressing air (which heats it up) and then allowing it to quickly decompress. Some of the air escapes, taking heat with it. The cycle is repeated until it is cold enough to liquefy. Then by fractional distillation oxygen and argon can be separated. When I said 'reduce the pressure' this is what I was referring to. Of course you would also have to compress it but the hard part is getting it cold enough.

  • @aaronakeller Oh so you're the teacher. Well yeah very misleading, poor kid was gonna hit the craziest vacuum just to get his solid piece lol. Very nice demonstration, what university is it? My chemistry teacher didn't demonstrate jack, although I have a good grip of the behaviors of matter. Hope u upload some more. ; )

  • @hitokiri657 It was actually a summer program for high school students. The program was held at Bowdoin College in Brunswick, ME.

  • you have to make the revolution of teachers, if even one hundredth teachers teach like you it would make students learn more

  • @aids696969 Nice of you to say so. I can't do fun stuff like this every day but I agree that it does help keep the students interested. And I like doing it.

  • ARE YOU related to helen Keller?

  • @hackerman237 No relation. Check the phone book: there are a lot of Kellers out there.

  • Nice! :D

    I've got a question though. As the teacher says at the ending: ''nitrogen has no oxigen in it so it doesn't allow things to burn'' So... Can nitrogen basicly be used for putting out fires? Or is it basicly the same as a fire extinguisher?

  • @TheBeyondNormalGirl Nitrogen could in principle be used to put out fires. Nitrogen as a liquid would flow uncontrollably and as a gas would not stay on a fire but carbon dioxide exits the extinguisher as a solid, which stays where it is put. This is probably why carbon dioxide is common in fire extinguishers but nitrogen is not.

  • Can I have half? XD

  • oh man your a cool teach!

  • You're a cool teacher!

  • my school is too strict and uncool to do anything like this... that is why i quit and I, am now teaching myself at a faster rate.

  • you look like louis c.k.

  • Very informative; I learned from this video! Thanks! 

  • "can i have half" lmao

  • Education is fuuun. ^^

  • i wish you're my teacher eventhough i dont take chemistry :)

  • @turtlepincher Nice of you to say so. Thanks!

  • Also known as the leidenfrost effect

  • @WoRtH1milli You may have noticed I have a video about the Leidenfrost effect.

  • actually I have poured some liquid on my bare hands before in science class but we touched it for less than a second and none of had frostbite haha lol

  • @WoRtH1milli You are correct, brief contact will not cause instant damage. I believe I posted a comment on the video about this...

  • At 2:00 it sounds like he's cooking hamburgers. :)

  • technically speaking, you CAN touch it, youll just lose your hand :D

  • "You can't touch it" is INCORRECT! You can pour liquid nitrogen over your open skin and nothing would happen. Damage is done when the liquid is stagnant, like if you were to cup it in your hand.

  • @dannycurtean I know that. See my annotation right in the video at 0:32. Also, see my other video by the title of The Leidenfrost Effect. It is posted as a response to this video.

  • I feel like i'm watching an episode of Myth Busters! <3 Great lesson... I wish my teachers were just as dedicated....

  • if it wernt for the leidenfrst affect i'cd onlyu have 3 fkngers

  • How does solid N2 require you to "lower the pressure?!?"

    I believe you must cool N2 and apply a great amount of pressure!