Reacting Fluorine with Caesium - First Time on Camera
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- čas přidán 26. 12. 2012
- In preparation for the 2012 Christmas Lectures Dr Peter Wothers heads off to the University of Leicester to conduct an extraordinary experiment - reacting the most reactive metal in the periodic table (Caesium) with the most reactive non-metal (Fluorine).
Due to the extreme reactivity of the two elements, Fluorine expert Professor Eric Hope is on hand to enable the experiment to be conducted safely.
We believe this is the first time the reaction has been caught on camera.
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Thank you, our Swedish friend, for translating this video into one of our favourite Nordic languages. Tack så mycket!
The Royal Institution , please explain what each element is actually used for, thanks.
But but but what are the reaction products?! This was nice but a bit too short IMO, some details about the reaction would have been nice.
I represent a Lithuanian company, which sells cesium 99.99 we are looking for buyers. if you find a buyer you are from the sale
get a percentage.
If you have any other questions, please feel free to ask them.
@@HMan2828 It's obviously Cesium Fluoride(CsF)
Francium has a half life of 22 minutes. Nuff said.
And now, You have created one of the most stable compounds, Caesium Fluoride, good luck freeing the caesium again without a lot of hard work from that, though I have to say I have always wanted to see this reaction. Made my day.
Actually, CsF is so ionic and the differential in charge is so great that is not that stable
@@thetaintpainter5443 huh, interesting
There is a simple answer to that - electrolysis.
Lithium fluoride would be even more stable, because lithium is much smaller, so the ions can get much closer together and therefore be held together more strongly by their opposite charges. Lithium fluoride has a standard enthalpy of formation -616 kJ/mol as opposed to cesium fluoride having a standard enthalpy of formation -553.5 kJ/mol. (I would have given the Gibbs free energy of formation, but I couldn't find it off the bat for lithium fluoride; for cesium fluoride it isn't very different from the standard enthalpy of formation.) And lithium fluoride binds to itself so well that it doesn't dissolve very well in water, whereas ridiculous amounts of cesium fluoride dissolve in water.
Cesium iodide?
"Why have I come up to Leicester?" Not the first person to ask that question I'm sure...
To see champions league football I should think.
A question often asked, yet, alas - can never truly be answered ......
for anyone searching for the music, it’s decisions by kevin macleod.
To see the body of King Richard III who was found by Ms. Philippa Langley. Congratulations, and all honor forever to her. Doctor George Whitehead
The board gaming convention Manorcon is in Leicester. A niche reason is still a reason.
Although it sounds counter-intuitive, Caesium is actually more reactive than Francium. Caesium actually has a lower ionisation energy than Francium (~392.811 kJ/mol for Francium and ~375.7041 kJ/mol for caesium). This is thought to be due to relativistic effects - have a google search around the subject, very interesting!
The Royal Institution The pattern has also been observed between Barium and Radium.
The internet is NOT the property of google; just say do an internet search, don't assign any proprietary terms to it, thank you
@@ITILII no
ITILII you got offended by nothing
@@ITILII I mean, do you call a tissue a Kleenex or a copier a Xerox? Is soda Coke to you? If so, you're a hypocrite.
Now it has to be like mythbusters and upscale the reaction to 10kg cesium and 20L fluorine gas :p
Mythbusters is rookie science, dude
BloodCrisis BloodSoul Zombie Feynman disagrees with you. xkcd.com/397/
Yeah, but brainless experiences lead to nowhere. I'm not a fan of theoretical science only; but they are not true scientist just artists, and you can see many of they experiments aren't well conduced.
BloodCrisis BloodSoul Did you click the link?
You're right, but as you say only "the beginning"
260 people were hoping for a big explosion, and perhaps a bit of injury. ;)
+James Wilkins I was surprised - I though it would explode. Cesium is extremely violent when dropped into water. It goes "bang." I thought fluorine might go "BANG!"
+Mod MINI The bang comes form the hydrogen gas released that then combusts with oxygen in the air. The cesium is just really effective at tearing the oxygen away from the hydrogen in water, which generates heat which then in turn ignites the hydrogen.
+lockerboy13 recently disproven - its actually a coulombic explosion
Kevin Miedema Huh, wonder if that's something that my chemistry teachers have always just glossed over.
+lockerboy13 nah its a relatively unknown phenomena, simply put the chemical reaction shouldn't create a rapid explosion (as thunderf00t showed in his videos) its only recently been well observed exactly how this happens
Could this be considered a reaction video? :P
I'll show myself out.
+blarg2429 Fine bros: It still counts! TAKE IT DOWN
Ahhhhhhhhhhhhhhhhhhh... very good.
Good meme
Like for dad joke.
Dr Wothers himself makes the joke (unintentionally) at 1:16 "What was your first REACTION when I said..."
At Clemson University in South Carolina a fluorine chemist has lost an arm and several fingers during his grad days working with fluorine. According to my teacher when she went there she could often here explosions coming from the fluorine lab.
"Hexanitro? Say what? I’d call for all the chemists who’ve ever worked with a hexanitro compound to raise their hands, but that might be assuming too much about the limb-to-chemist ratio."
blogs.sciencemag.org/pipeline/archives/2011/11/11/things_i_wont_work_with_hexanitrohexaazaisowurtzitane
Poor scientist :'-(
hear*
May I just say that both of you professors are absolutely insane for doing this. With that said, that was interesting.
To the person who just translated this, and a whole bunch of our other videos, into Portuguese, obrigado!!!! Thanks so much, we really, really appreciate it!
If anyone else wants to contribute translations, to help make our videos available to more people around the world, please jump right in: czcams.com/users/timedtext_cs_panel?c=UCYeF244yNGuFefuFKqxIAXw&tab=2
You're welcome :-)
So, was the product of the reaction analyzed? Did you end up with cesium fluoride? What was the yield? At what pressure would CsF3 be possible? So many questions, so little money to pay for university....
@@HMan2828Not many people get to use it unfortunately, even past university I’ve heard. It’s a bit too reactive unfortunately.
The most electronegative element with the least one.
Wait, I'm a beginning chemist and maybe some of the stuff i've been taught is false, but isn't Francium the least electronegative?
@@venomoussloth5092 no
@@venomoussloth5092 Just studying the trends won't help....There are some anamolous properties in the groups and periods... Mostly because of their electronic configuration and their half/full symmetric configurations
@@darkgreninja8349 Why no, Francium is the least electronegative
@@venomoussloth5092 maybe because Francium is radioactive and it decays. Idk honestly as I'm a 10th grade student :-)
Thirty years ago I worked for a company that among other things bought military surplus. The boss had gotten this strange ball made of stainless steel about the size of a softball, It had some fittings and rods coming out of it and looked a lot like the Sputnik spacecraft, It was obviously hollow and had some liquid in it. He and another employee got to work trying to cut it open. After a lot of hack sawing on the thing, they cut through and a silver liquid metal started pouring out. This surprised them and they tried to catch it in their hands thinking it was mercury. There was not much, about what the video showed. It started burning their skin and smoking. They ran to the sink to wash it off with water. When the water hit the metal, now stuck to their hands, it caught fire and exploded in small pops and fizzes. We later learned that it was caesium. Their hands healed after a few weeks.
Later I did some research and to my best guess, the ball was indeed a satellite that the military used as a target in orbit to aim high energy xray beams at. This one never made it to space and ended up being sold (most likely by accident) at a surplus sale.
Well, that wasn't very smart.
Wasn't very smart to sell a ball full of caesium or to get it on your hands? I must admit I was a little amused by the whole thing. I did not like my boss very well.
To get it on your hands. There was an accident in Brazil I think, where a man has found a weird looking metal cylinder. After opening it (it took some time) he noticed there is a blue glowing metal inside. Long story short, it circulated between tons of people and it happened to be radioactive, causing tons of deaths.
Piotr Joniec Ah, the Goiânia accident.
It wasn't a metal, it was a radioactive caesium chloride salt that had been used as a gamma source for radiotherapy in a hospital.
It wasn't tonnes of people who died, it was 4. Which might be surprising since it contained 93 grams (!!!!!) of ceasium-137 chloride and it was handled with a kind of unfathomable recklessness that seems surreal still today.
He took the source in its container from it's shielding and brought it into his house and invited everyone to come and see it. Then they took turns using a screwdriver to chip out several rice-grained sized chunks of caesium-salt as well as scraping out dust and _shared it around with friends and family_. The person who found it _intended to make a ring of it for his wife_. One of the kids rubbed the stuff all over her arms so that she sparkled. His brother _painted a cross_ on his stomach using the dust. Some of it was _eaten_ by mistake. It ended up on bed clothes and every where else. It wasn't until 15 days later that the source was transported to a hospital so that it could be examined, in a plastic bag, _without shielding_, using _public transportation_.
+Piotr Joniec Co60 I'm sure.
There wasn't any audible noise produced from the reaction - just the beautiful light given off! They needed a pure sample of Cs for this experiment and it can be quite difficult to isolate because it is so reactive - it's makes it quite dangerous to handle as well!
Just like sodium and potassium are stored in kerosene, was caesium also stored in kerosene???
@@bhoomipurohit_nd5_em802 no, its stored in a glass capsule, in a vacuum coz it can melt at slightly above the room temperature
Who else came here immediately after learning about periodic trends? I’m here but I need to study for my chem final:p
Me too! I study in 10th grade. What's your grade?
Well, this is an interesting coincidence.
Ya
Well, it’s quite counterintuitive for cesium to have a lower electronegativity than francium, despite it being above francium
This is true love in the periodic table, yin and yang.
The one that wants the electrical charge most and the one that wants most to give it's charge away.
I was a student at Leicester. The video brought back great memories of those buildings! Amazing!
Thanks to our amazing French friend, you can all now enjoy this video with French captions. Merci beaucoup!
That was quite a light.
Now you are become death, the destroyer of labs.
Did you measure anything? Anything at all?
clever wordplay 😂
Qualitative measurements
well, It was just a small qualitative experiment. The quantity was not In the spotlight.
01:25 am I the only one who thinks one of them should have said "No pun intended," after he says "That'd probably be most people's reaction?"
I thought the same thing xD
+MrBurkeGames WOW that's fuckin weird. Haha.
Benzene Reactions I like your name :D
+MrBurkeGames When he asked "what was your reaction...?" I was expecting the professor to respond with something like, "nothing compared to what we're about to see."
thats what light sabers are made out of
absolute madlad
@LukeMichalowski, totally right
Madlad
i'm a 12th grade student, i love chemistry, however i wondered how would the reaction look like and this bought me here... feels so satisfying🤗🤗
The concept of this reaction makes me cringe in fear. Watching it done makes me even more scared. Thank you for performing it so that I didn't have to! I kind of enjoy being alive
well hey we get a salt out of it... halogens and alkali metals make salt right... or at least a type of salt not necessarily NaCl
The Shishlord k thanks all i knew when i posted that was alkalia metals and halogens make salts
Judging from this video. Anything could be going on. It might not have even been the chemicals mentioned :\
bad video.
It's exactly the same compound. Reacting caesium with fluorine gives caesium fluoride. You do not have to have an acid-base reaction to make a salt.
Fluorine, chlorine, bromine, and iodine (all of column 17 of the periodic table) are called halogens. The word "halogen" is Latin for "salt maker". The vast majority of salts are going to be fluorides, chlorides, bromides, and iodides.
Cs + F= CsF + A lot of f'ing heat, photons, and other good stuff. :)
This is what I was looking for amongst the comments... CZcams comments are such a cesspool.
Don't forget fluorine is diatomic :)
stormonmormon14 Rou're god damn right! 2 Cs + F2 => 2 CsF + Two times the lot of f'ing heat, photons, and other good stuff... :)
2Cs + F2 = 2CsF
And creates one of the most ionic compounds!
Dr Wothers made a comment about this on Twitter stating: "Before anyone asks, francium is not as reactive as caesium. Cs has lowest ionization energy of all elements"
As a kid doing chemistry at school in the late 90s, this is the reaction I wanted to see!
3:59 You’re welcome
Holy hell Im in love with that periodic table at the beginning. Its so cool to actually be able to see each element.
The biggest “wow” for me was that the periodic table has a vial of fluorine. Someone must have spent a lot of time making that happen. You can’t just put fluorine into a vial - it’ll eat its way out. That glass must have been treated so that there’d be a passivated layer that had some self-healing properties. Kudos to whoever pulled that off. It takes lots of care. Contaminants will act as bridges that will cut through passivation and make a hole in the glass eventually (or quickly, depending on what the contaminant is). This is the sort of stuff where plain old dust from the air can mess things up.
Unless it’s just a vial filled with air. Should be easy to test - fluorine has lots of absorption lines in the visible spectrum, a hand held spectrophotometer should be enough to tell perhaps. Even stronger lines in IR if I recall right.
I love that line: "I thought you were totally and utterly mad."
Based on the intense violet white, I'm wondering what the emission spectrum was since there was almost certainly a substantial UV component
The most electronegative combined the least electronegative, producing the strongest bond?
I think???
This video should be called EPIC. Fior me in my teaching practice it is a breakthrough. Peter and team thank you so much. You all really rock chemistry demo's. Please introduce more questions at the end for students to wonder and think and structure their knowledge on this type of reaction.
Did anyone take a spectrum of the light? That would have been pretty cool!
Or hot?
I'd bet at least some UV, would hope for X-ray but I doubt it :P
x-rays are at least 3-4 times the energy per photon than even the most energetic chemical reactions can emit. The energy of emitted photons can never exceed the energy of a single electron transition in a reaction.
Fluoralantimonic acid the nope acid
@@dustinbrueggemann1875 even so, that would allow some pretty hard UV to be created. It would be fairly impressive.
2:18 "we all know how hard it is to cause this to react with the oxygen in the air" (actually it's pretty damn simple)
"imagine how easy it would be if it was fluorine."
(some people just want to watch to world burn...)
ITS FLUORINE NOT FLURINE GODDAMNIT
It's a lift, not an elevator.
+Night Angel That's a dumb name for something that elevates you. You would think you'd all it a "lifter" because it lifts you but no.
You know, tomacco tomacco.
Potayto potahto. tomayto tomahto ...let's call the whole thing off.
It's a footpath, not a sidewalk.
It's a road, not a pavement.
It's a car, not an automobile.
It's an aeroplane, not an airplane.
It's a torch, not a flashlight.
It's a shop, not a store.
It's English. Spoken by English people. U/S citizens usually speak American English.
Therein lies the truth; we're two nations, separated by a common language. Arguing about it is pointless, and will cause ill-feeling and xenophobia.
We're all human beings, and our languages should be used for communication, not for dissent.
caesium is the most reactive? first a spelling mistake I've had to live with for the past ten years and now this
+Matty Brumby im not sure what im meant to be getting over...
+smzig he called it alumium first.
+Matty Crumby It's also pronounced Leister. :-)
+Matty Brumby I didn't know and many others are probably surprised as well.
Actually it's pronounced Lester
The longest half-life of any isotope of francium is about 22 minutes. It's likely that a few people that have studied it in depth have seen a milligram, but not too many. At any given time, there is approximately 20-30 grams naturally in the entire world.
Incredible! You earned another subscriber!
I admit I am surprised at how anti-climactic that was. I expected a violent explosion from those two. Granted, I am grateful for the video. I've always wanted to try it, but I expected to blow my face off so I haven't.
The reason why there's no explosion is because there is no hydrogen being produced as is the case when you drop a period 1 element into water.
Beautiful.
I've never seen this before and it's so amazing.
Great video, thanks for the demonstration! :)
Chemical reactions happen more slowly at cold temperatures. I'd love to see what happens when a pin made of cesium is slowly pushed into a small disk of frozen fluorine while all this is submerged in liquid helium. Would it react with a simple touch? or would a little twisting of the pin be needed?
that sounds like boom
It would create the molecule CsFHe. That’s what they make that impervious super tough plastic used to seal any household product that you can never open.
Skip to 4:10 for actual reaction.
So the first 4 minutes of the video are completely unnecessary. Typical.
@@MichaelTheRead i found them pretty interesting
The grin on my face while i was watching this. Priceless!!
Absolutely fascinating. Thank you
Now that you got cesium fluoride, does it make the most non-reactive substance ever, considering there's nothing more reactive to displace any of the ions?
a great question out here!
@sharpfang No, but I think it makes it the most ionic compound in the world. As for reactivity, I bet it would still react with water to produce some hydrogen fluoride, so it's far from unreactive.
Such...a...beutiful...flame...
Sehr interessant, selten was so spannendes gesehen…
He still giving heart after 8 years. What an youtuber.
Thank u very much for making this video
rt if u came here after googling francium and fluorine
rt
Y'all better hope the FineBros aren't watching...
They'll copyright this reaction video
Thanks a lot! This was a reaction i really wanted to see :)
A genuine, honest-to-goodness mad scientist!
WOW Fluorine and Caesium are pretty salty when they meet each other
gradevoir yes!! I ship them hard!
Periodic table is made brilliantly
Wow! Thanks for posting!
I was expecting something a bit more spectacular between the two elements that would most readily react with one another, I'd always wondered what it would look like.
Can someone explain why some people say Cesium is more reactive than Francium? I know Francium is radioactive and decay so fast but that's not the reason. Cesium has less ionization energy than francium (that may be the cause)
It might not be. Its just we can't really make enough francium for long enough to do anything with it.
Alternatively, relativistic contractions in this low area of the periodic table lead to a shrinking of the increase in atomic radii expected down the group, slightly reducing reactivity.
I am, well aware of that. Though I would link it more to a relatavisitc effect caused by the electrons in a 7s orbital having a non zero probability at the nucleus combined with a high nuclear charge and the electrons moving close to the speed of light causing a contraction. The lanthanide contraction is more appropriate to the 6p elements, as by 7s they have become basically core-like.
Isobel Priest i'm a little bit confused, can't the decay be stopped if it doesn't have contact with certain substances, e.g if it was left in a vacuum?
Decay of what? The fact its less reactive is a physical property, the orbitals of the electrons are set. Radioactive decay: also no, half-life is a property of the molecule, and not generally reaction dependent.
Wow dumb it down some more! Why not go though a little bit of theory at the end.. Like what compound did it make and why
+HomeDistiller Cs+F=CsF
+1luv4j
2Cs + F2 => 2CsF*
fluorine has to be one of my favorite elements. the stuff just won't sit still. its like the ADD kid in the neighborhood that everyone hides from.
Excellent video quality
The tube didn't even explode. Lame.
peterpan260983 to be fair, they planned it that way... Escaping fluorine has a good chance of turning to gaseous hydrofluoric acid, and caesium more-or-less blows up on contact w/moisture, so escaping reagents here could've very easily been deadly.
(I do agree, it looked a bit anticlimactic, however)
Is francium just a theory or does it actually exist?
+Jermaine Lee Of course Francium exists, there couldn't just be a random gap in the periodic table.
+Jermaine Lee Francium only has a half life of like 45 minutes. If you need Francium, you have to get some radioactive Thorium. As it decays, it turns into Francium briefly and then that Francium turns into other things. Not terribly useful!
+Jermaine Lee essentialy it exists but it's one of those elements that just doesn't like to exist.
+Jermaine Lee It exists. Technically.
It exists, technically and literally. You just won't be able to find much.
Great video!
Oh, how I do wish you captured spectra! Wonderful regardless
It didn't blow up!
D:
I was actually expecting that too...
really enjoyed this video
This is my favorite kind of reaction video
this helps a lot with my project
I love the intro. That's done with those superabsorbant polymer balls. I have some of them and they're awesome
that was awesome you guys should do more reactions with Caesium
I'm happy because it is in my recommendation.
the reaction stage skipped fire and went strake to plasma, you could even see eletrical sparks forming with what appeared to be some ultraviolet light coming off the reaction.
OMG this is the most craziest and exiting thing EVER
This video really deserves more attention and likes.
shush
Thanks to this, I can finally do my Research Project🎉
3:58 Me: YES FINALLY THIS IS GONNA BE SO AWESOME
4:05 Me: oh..
I wanted to see this for a long time.
Is this the most chemical energy possible?
Thanks for posting!
There’s an important distinction to be made here between differing notions of chemical reactivity. Yes, cesium has the lowest ionization energy of the group 1 metals, but from a thermochemical standpoint that only makes for a low activation energy. This is why you see cesium ignite in air (under high humidity and prompt exposure) and explode so rapidly on contact with water. HOWEVER, the thermochemistry also goes to show that the large ionic radius works against cesium’s enthalpy of reaction with many other elements. In other words, the large size of the cesium atom prevents it from bonding as tightly, and in turn cesium releases less energy per atom/mole in most reactions when compared to all the other group 1 metals. If you don’t believe me, compare the condensed phase enthalpy of formations for all the alkali fluorides on NIST - lithium takes the cake on a per atom basis AND on a per gram basis. This is all not even touching on the fact that and atom of cesium weighs a lot more than lithium, about 20x more.
The significance of this is that an equivalent mass of lithium replacing the cesium in this shown reaction would produce 21.23 times more heat reacting with fluorine. Considering that fluorine will react violently with any alkali, and heat will only accelerate the reaction by making it more spontaneous, it is safe to say that a you would see a much more exciting show if you used lithium over cesium.
I always wanted to see this reaction
I've just realized something. This music when they were setting up the caesium, it's used in SpaceChem as the background music.
Wonderfull example of more energy is released when a bond is make, than a bond being broken.
You are correct, because the outmost electron in Francium is held tighter then normal.
releasing fluorine into the room and not using a fume hood is crazy
Nice explanation
Breaking news: two researchers died this morning working with both cesium and fluorine. Two bodies were found, but not identified. It is unclear what they were attempting to accomplish.
The flame was bright enough that any color wasn't seen in the unfiltered frames, but in the filtered, the purple of exited cesium atoms could be seen.
Professor Eric Hope looked absolutely terrified from his absolute first shot
Appreciate the info. Nice to learn something new.
What a magnificent reaction
This is the same fluorine scientist from the old periodic videos video! Seems like he’s the only to have lasted the study!
Wow - thank you!
Anyone noticed sparks of electricity right before the light. Well that was the electrons escaping cesium through the air into fluorine indicating the extreme affinity of both of them to each other
Aka Plasma
He's the same professor of the periodic videos' fluorine video :D
That guy 's getting famous real quick
You should cool some compressed Fluorine in to a liquid with some liquid Nitrogen then, with a syringe, add some a drop of Caesium, warmed up enough so that it's a liquid.
You can just imagine the cesium and fluorine atoms both saying as they met each other: "holy S***!"
Moral of the video:
Don't judge a chemical reaction in a youtube video through its thumbnail preview.
"Hope" is a good name for someone who works with fluorine.
That's REALY cool!
DAT PERIODIC TABLE ON THE WALL *-* :O
Reaction lasted longer than I expected