The shelves quietly burning in the background was a nice touch.

legend has it the prefessor has been sitting in the room for 24 weeks now

@yeetdosis39

3 жыл бұрын

For quarantine, I guess hahaha

@WineScrounger

3 жыл бұрын

He seems like he’s ok. He’s got plenty to read after all. Be well Professor 😺

@johnladuke6475

3 жыл бұрын

I hope someone is coming by each day to water him and turn him toward the sun.

Exploding bags of chlorine made me say "Wow!", and then "Why's he doing it right over the fire exit!?"

@Vokabre

3 жыл бұрын

Makes perfect sense! That's if there's fire the fire could exit via fire exit.

@chrishughes3405

3 жыл бұрын

The ironing is delicious

@johnladuke6475

3 жыл бұрын

Because it would amuse Neil to see all the foolish flammable mortals trapped as the building burns down and leaves him behind, standing, smiling, bald, eternal.

Exploding bags of chlorine? Now you're talking my language!

@Ramian1

3 жыл бұрын

What?

@olmostgudinaf8100

3 жыл бұрын

I was wondering about that. He was spraying hydrochloric acid on the nice lacquered wood cladding with that experiment. The university board must have been thrilled.

@RobertBardos

3 жыл бұрын

Bet it smelled nasty

@SuperAnatolli

3 жыл бұрын

Yeah! I was just scrolling through the U-tube recomendations and spotted the word "exploding" in the headline. Suits perfect a thursday evening, a must-clicker!

@synthesizer8026

3 жыл бұрын

I love the small of chlorine in the morning, lol

So, lotteries tend to be endothermic since the number of tickets you'd have to buy to ensure a win typically costs more than you'd win.

@BooBaddyBig

3 жыл бұрын

Yup. Except on some roll-over weeks where they become exothermic.

@TheGreatAtario

3 жыл бұрын

Endonumismatic

A hugely important example of a catalyzed reaction that has has huge activation energy but is also endothermic is the Haber-Bosch ammonia synthesis process. It's one of the most important discoveries in history, and has led to the 1-2 BILLION people (maybe more) being able to survive by making it possible to effectively pull nitrogen out of the air and put it back into the ground to be used as fertilizer. 3H2 + N2 = 2NH3 is an exothermic reaction, but it has such a high activation energy that it was basically impossible to keep it self-sustaining with heat alone. Haber discovered that an iron catalyst reduced the activation energy enough to allow the reaction to proceed at manageable conditions. Bosch is the one that scaled it up from bench scale experiments to industrial scale. This was over 100 years ago. It's one heck of an extreme setup to make this happen. It's been a while since I built one of these, but if I remember correctly, temperatures in the reactor need to be anywhere from 900-1000F (482-538C) WITH the catalyst just to keep reaction going, because of the high activation energy. However, once you do get the reaction going, because it's exothermic, the heat released from the reaction sustains the reaction. Thus, you need some sort of independent source of heat (we used electric heaters) to initially kick off the reaction, but then you switch them offline when the reaction gets going and the system stabilizes. It was an interesting engineering challenge, that's for sure. Even though the temps have to be that high, you want them to be as low as you can get, because the equilibrium ammonia yields are favored by lower temperatures because the reaction is exothermic. Because the number of product moles is half that of the reactant moles, higher pressures also favor greater yield. I think our reactor operated at 950F (510C) and around 2000 psi (138 bar), but probably 50% higher pressures would be preferable. There's are serious pressure vessel considerations when operating at considerations like that, though. The reactor has to be at least 9-Cr, 1-Mo steel to resist hydrogen embrittlement which increases with temperature. 304 or 316 stainless have better embrittlement resistance but have lower tensile strength, meaning a thicker vessel. And stainless may cost more depending on availability of materials. And then there's the fact that you have to cool the product stream down to about -20F (-29C) to liquefy and remove the ammonia before recycling the unreacted H2 and N2 back to the reactor and having to heat it back up to 950F. Lots of staged heat exchangers. I basically designed and supervised the building of that entire system (it was a pilot plant but still fully functioning) myself...at the age of 27-28. That's not to flex on others; that's to say to my fellow engineers that you can do amazing things if you're willing to put in the effort to learn what's going on. Don't let anyone tell you that you that something's beyond your grasp. You'd be amazed how much you can learn if you just open a book and then keep asking yourself "And how does this work? And this. And this."

@thetransformatorium7980

3 жыл бұрын

I would give this comment a thousand likes if I could! Cheers! 😎

@AnonNopleb

3 жыл бұрын

Amazing comment should be pinned. Thanks for the insight to the complications and considerations that have to be made when actually taking a reaction from theory to technical application. To get a bit furher into theory, the main problem with the Haber-Bosch-process, taking the huge activation energy aside, is the negative reaction entropy, which sets a temperature limit to the whole reaction. Despite the use of a highly advanced catalyst and tremendous pressures, to get anywhere near useful reaction rates, engineers have to go to such lengths as to operate the reaction near this temperature limit, where the reaction reaches equilibrium very soon. So the cooling step is essential to separate the ammonia from the remaining hydrogen and nitrogen.

@Lucius_Chiaraviglio

Жыл бұрын

Typo in 1st sentence -- I think you meant exothermic where you have endothermic, like you have later.

The professor seems to be a catalyst for the chemistry outreach process.

That guy is amazing at asking questions lol

@dingaia

3 жыл бұрын

guess you can say he does a good job

Petition to get One Great VOOOSH! as an official measurement?

@dr.v645

3 жыл бұрын

No, that is how the United States got in the measurements mess it is in.

@Daisyboobs

3 жыл бұрын

I see a little silhouetto of a voosh. Millivoosh! Millivoosh! Will you do the Fandango? Thunderbolts and lightning very, very frightening me. (Nanovoosh) Nanovoosh (Gigavoosh) Gigavoosh 'cos it's metric, don't you know? Magnifico-o-o-o

@sarah53062

3 жыл бұрын

@@Daisyboobs wtf

@thomaslauer1015

3 жыл бұрын

@@Daisyboobs I laughed way too hard at this

@ekscalybur

3 жыл бұрын

@@Daisyboobs This was glorious, well done!

5:42. How to bring a smile to Neil's face.

@Willam_J

3 жыл бұрын

runcycleskixc - He actually laughed at 5:23 I had to watch it twice, just to make sure. 😆

Never knew liquid O2 was magnetic. You learn something new every day. :-)

@jonahansen

3 жыл бұрын

Doesn't have to be liquid, either, but it's hard to see it with the gas.

@WineScrounger

3 жыл бұрын

Well, paramagnetic but it’s still fun

@mehmedcanozkan3268

3 жыл бұрын

In fact, almost everything is, just not ferromagnetic. Look into diamagnetism and paramagnetism! Some elements repel and some attract magnets, although very weak:) We have all been thought its only nickel, iron cobalt that we can get action... but that’s not it!

@terrodar19

2 жыл бұрын

You can figure that out basically for any simple molecule like O2 by drawing its Molecular orbital chart. if u got some sophisticated computer program you can do it for much more complicated ones (those are scary to look at)

So happy to see Professor Poliakov! Hope to see him more !

@Feyangel23

3 жыл бұрын

ditto 😀

@jaik195701

3 жыл бұрын

Sir Martyn

@michaelsheffield6852

3 жыл бұрын

he is refreshing.

@alanna4858

3 жыл бұрын

I’ve been subscribed to this channel for so long 😂 but always click fast for him.

Students who don't study, either have high activation energy levels or do not contain energy inside.

@Feyangel23

3 жыл бұрын

ahh Schrödinger's student

@GeFlixes

3 жыл бұрын

Ah yes, the two banes of productivity: Procrastrination and depression.

@Kenionatus

3 жыл бұрын

No teacher likes the endothermic students.

@cdl0

3 жыл бұрын

From a physicist's viewpoint, it is also possible that these students who don't study have a very large moment of inertia. Their centre of gravity is likely to be the local student bar. :-)

@BlackSakura33

3 жыл бұрын

I will use this when I teach

"and the answer is..." The professor's hair emits a fire supression field?

1:54 Dinosaurs Attack card being burned, I'll take that as a Hi to the Tims! Why card #25 though? Feel like the classic #5 Homeroom Horror would be more fitting.

@leppeppel

3 жыл бұрын

Or #8, Crushing a Canine

@doomedmessenger

3 жыл бұрын

Here I was wondering if that was now going to be sent to someone. ^^

Neil is one of the most fascinating and mysterious figures of youtube and I wonder if he knows it

This is amazing. Wish someone had explained this so simply in high school chemistry.

This was an excellent question. It's essentially the difference between rusting or burning-one is slow, the other is vigorously self-sustaining. The autoignition temperature is also quite interesting.

ITS NEIL AGAIN! Havn't seen Neil for a long time!

@xenonram

3 жыл бұрын

Neil is on almost every video.

@InfiniteWonderz2

3 жыл бұрын

@@xenonram Havn't seen Neil for awhile

My favorite exothermic professor!

@5:42 Seeing Neil standing there, calmly smiling at a ferocious reaction at arms length, is both reassuring of him knowing what he is doing, but also a bit frightening. What on earth can make him look nervous or excised? Nice video and topic. Much appreciated. Seeing Neil is always a charming treat too, especially when he can be seen wearing those boots.

This topic was a harder one to me to understand . This video helped me to get it fully understand clearly and easily.

This was an awesome video. It was all made so clear. I wish I'd had access to this kind of resource when studying chemistry at school.

I really like how Periodic Videos now have many videos about every topic, so they recomend many of their videos during every single video.

"Why doesn't my hair start burning?" Professor, your hair is already on fire.

Burning a collectible "Dinosaurs Attack!" card @1:23 -- sacrilegious!

As a chem major back in college, this was a nice throwback topic.

I knew all this from High School chemistry, but I haven't thought about it in 50 years. This is a great explaination!

Quite fascinating the chlorine bag reaction

You are a joy. Thank you so much

All together now: WOW!

2:03 I realize you have a lot of these cards, but this still seems cruel XD

@TimRrstrm

3 жыл бұрын

It is not just cruel, it's downright heresy!

this is awesome!! we learnt this in class just this Tuesday! Hopefully our teacher will allow us to do the chlorine reaction

This was a great video! Along with elements, can we get more videos on concepts like these ?

Great explanation! Thank you.

Professor Poliakoff is a treasure. Love him. ^^

Keep 'em coming Prof Pol!

I must say, I've been enjoying your channel for years now and I look forward to more years of videos. A video that I think would be a real winner is one on Liquid Helium. I think most people don't know much about it and it's uses, so it would be a really exciting video for all the current and future viewers.

Thank you for sharing. Charles

Great exposition. Thanks

Another great video thank you

Thanks, now I know something new and at last, I understand a chemistry class more than 40 years ago. Greetings from Venezuela.

excellent video, very informative.

I loved this video! More theory like this please

I feel a slight sense of pride in recognizing every single reference video used. :D Love your channel.

I'm sure this is some high school or 1st year university chemistry material but heck the Professor explained it so well

Wonderful video.

Love this channel

Love the video, i always enjoy them : )

Would be interested to hear more about catalysts and how they work (as hinted at here) and why they are often otherwise inert materials.

I like endothermic reactions. I love how simply mixing two things together can actually turn the mixture cold! It almost seems to violate the laws of thermodynamics because my first thought was that you can easily get that energy back out that was absorbed from the environment and repeat the process over and over. Turns out that isn't the case.

Thank you very much for this video. I am a firefighter from Germany and also trainer for our new recruits. Until now I had a really hard time to explain the catalytic and anti-catalytic effects, which are important for various methods of extingushing. Maybe there is a chance for a video explaining the anti-catalytic effects in general? I love your videos. Thank you!

A perfect way to start my day.

love these videos

I wondered about that question years. Then I considerd heat dissipation and the solution appeared more intuitive. Thermal noise may occasionally result in sufficiently energetic collisions to oxidize combustible molecules well below the combustion temperature, but the heat generated in those reactions dissipates too quickly to sustain a chain reaction.

@FarleyHillBilly

3 жыл бұрын

Never stand next to large quantities of high explosives.

That was a really great video. You guys should make more videos on other properties of chemicals, like enthalpy of formation, enthalpy of fusion, what enthalpy actually IS, vapor pressure, heat capacity, heat conduction, molar entropy and the list goes on. Heck, you guys could have an entire series just on these topics. And if you present them half as well as this video was done, it would make for some great binge watching.

Chemistry, Biology, and Physics are my favorite subjects in Science. I just started appreciating Chemistry

I love your videos! I hope that one day I can be a chemist, that comes close to you!

PROFESSOR I'M A HUGE FAN OF YOUR HAIR😂

It's just so relaxing listening to the Prof.. Even my girlfriend likes these videos. Even if she's not as familiar with neither chemistry nor english in general as I am :D

Wow..that's very interesting! Always leaning something new..thank you!:)

I miss Periodic Videos. I need 2 a week at least. Awesome fireplace Brady. Needs some "activation energy" in it this winter mate.

So excited for another video with the Professor! Tell us more about the chemistry of catalysts!! Why Platinum? There are many elements with unpaired electrons. I know it's one of the elements used in our catalytic converters.

I love this professor

How old is the professor now? He will go down in history as the best teacher I never had

@willydiaz9586

3 жыл бұрын

he's 86

I'm glad you're okay!

I love this man.

Great sir..sir please make video on colours of elements and reason behind it

I'm happy ! Years ago I asked Pete License to perform the reaction between Hydrogen and Clorine gas. Now I saw it ! Neil congratulations !

9:56 "VOOSH!"

@sam08g16

3 жыл бұрын

Holy sh... I read your comment EXACTLY when he said it!

The professor is fireproof.

"When you eat a jelly baby/gummy bear, you eventually convert it to Carbon dioxide and water. But flames don't come out of your mouth." This is by far the professor's best anecdote.

@robertwilloughby8050

2 жыл бұрын

Unless you have GERD, then you FEEL you have flames coming out of your mouth. (Said as an occasional GERD sufferer!)

Professor I am the greatest fan of you

i watched your entire playlist of periodic table of elephants, and saw this i got excited.

This reminds me of a video Richard Feynman did where he explained this and transitioned seamlessly into explaining how trees grow out of the air.

Music at the end was soothing

If Professor Sir Martyn is my online class teacher, I would never miss one

Your fro on point bruh

"Jelly Babies", now that's something I've never heard before. : P

@SGT_Fon

3 жыл бұрын

Need to watch more Dr. WHO...

@johno9507

3 жыл бұрын

@@SGT_Fon Hahaha I was thinking the same thing.

@Aphelia.

3 жыл бұрын

Unexpectedly gory...

@joshuarosen6242

3 жыл бұрын

They aren't really the same as gummi bears. They are, as their name suggests, more jelly-like. They are a popular delicacy in the UK. I became a vegetarian in my late 20s and jelly babies are really the only thing I miss.

@greensteve9307

3 жыл бұрын

What planet are you one?

speaking of platinum being a catalyst, is this the same for iridium, copper and other metals used in spark plugs?

Again you get my attention. 👏👏👏👏👏👏👏👏👀👁️✅ Next video? Try: Film vaults can light off the same way. If the atmosphere is conducive, the film stock will spontaneously combust.

Neil is so completely unphased by his exploding bags hahaha Also huge props to the editor for lighting those books on fire in the beginning

Please make more videos on organic chemistry, ones with green coats.

Damn, there are a lot of books on your shelf. Have your read them all?

01:54 Burning a copy (or illustration thereof) of Ray Bradbury's _Fahrenheit 451_ would have been apt.

@davejacobsen3014

3 жыл бұрын

Just what I was thinking!

Anyone else thought the chlorine bags have some senior prank potential ?

AWESOME Reactions on this Chemistry-Videos!!!

Is there an episode on katalysis? I would love to see a dedicated episode.

So the activation energy needed changes per reaction, but does it change in the environment it's in? Or would the environment be counted under a catalyst?

The paper burns spontaneously but it is too slow to observe (due to small no. of molecules possessing energy). That's why very old paper turns a bit of yellow.

"Have you ever wondered, 'Why am I not burning?" Well I certainly have now

This would make a nice primer for an episode on hypergolic mixtures.

Is it the oxygen that's magnetic at those low temps or could it be the glass tube the oxygenis in? Just curious.

Could Professor Poliakoff do a video on molar calculations? It's an area of chemistry that I've struggled with since school and I'm trying to reacquaint myself with the topic.

I'm pretty sure that safety matches (the kind that requires the striker as shown in the video) have much more going on in there - perhaps enough to warrant a separate video?

Has there been a video on phosphorescence?

can any form of energy start the reaction? so reactions just need less thermal energy to start than mechanical. or the kind of energy plays a role?

Can someone please provide a pdf of the periodic table professor shows sometimes in element videos? Thanks!

If not for Periodic Videos, I would never know that a group of jelly babies (gummy bears) is known as a “chorus”.

What is the wavelength of the laser used for exploding the Chlorine-Hydrogen bag and is it a laser at all?

@jimurrata6785

3 жыл бұрын

Just a photo flash is enough. You don't need a collimated beam