We're all on the government's list now, man.

This man looks like science

I could listen to this guy all day. I wish I had someone as interesting as this when I was at school. What a legend.

i am officially closer to nuclear weapons than north korea

the puffy hair makes him look more legit.

If people like the Professor and his colleagues were on TV more often than some of the 'science journalists', the public would be much better informed about these sort of issues. Please keep up the good work!

I respect Professor Martyn Poliakoff for explaining these processes in as much detail as possible within the time allotted, and without witholding key knowledge. Other authors here would rather experience and learn 'for' us, and only film the results to boast about what they have obtained in dangerous experiments. The Professor didn't as us a membership of his college, or certain prior knowledge or experience with materials, which is unlike how it usually happens.

I love how the Prof's glasses double as safety goggles, that is a dedicated man. Always enjoy listening to him explain things, very articulate and easy to understand. As always, very informative video!

This man is science in human form.

7:41 "I think like a lot of things in life the basic idea is really simple, but actually executing it, so you don't end up with clouds of radioactife UF6 pouring all over the place is actually not trivial." I totally hear you. :-D

Well darn, there goes my weekend science project with the kids. I guess its plan B, make some triazadienyl fluoride.

Thanks for all the videos you've made for us prof. I greatly enjoy them and find them so informative! Much love from California, US.

I love science! Videos like this inspire me to learn all that I can and do better in my studies. Thanks, periodicvideos.

depleted Uranium is used in aircraft as a mass balance weight for flight controls to control high speed "flutter". uncontrolled flight control flutter can destroy an aircraft in seconds. (search on youtube for vids) so depleted uranium is used to ensure everything is balanced, and hence, stop flutter.

Not if you want to make bombs but U238 was, in fact, weaponized. U238 is heavier and has higher density then Lead so military used it to make armor piercing ammunition and heavier ordnance because, being heavier, depleted uranium projectile carries more kinetic energy and it's hardness allows it to pierce hard materials(like armor) instead of squashing itself on them like lead projectiles do.

Depleted uranium is used both in ammo, specically in antitank, and in armor. It is used for its density, and in the case of armor piercing ammmo, for its incendiary properties.

Another fantastically informative video! Loved it! Thanks guys!!

Uranium and fluorine.. who the hell got that idea ? hahah sounds like a scary compound.

As always, wonderful video. Thank you for posting.

Typically 90%+ is concidered weapons grade. You don't need much of it to make a bomb, but it needs to be close to pure U235 in order for the bomb to be effective. By comparison, 5% U235 would be perfectly suitable for a reactor. So you can quite easily tell the difference between weapons and reactor grade, you won't "accidentally" make weapons grade stuff.

Man these videos are awesome! and this is my favourite one so far! Keep up the great work :)

Weapons grade uranium makes a perfectly stable and controllable reactor. In fact, it tends to have a more negative temperature coefficient of reactivity than commercial grade.

I would go to study in the University of Nottingham just to study under this scientist... very easy listen to and knows EXACTLY what he is talking about, and could put Uranium enrichment considerations into complete layman's terms so anyone could understand it, which is an important aspect of being a great scientist. great channel, subbed

The photo of the Manhattan Project enrichment facility was actually a photo of the calutron, which was basically a huge mass spectrometer. It worked by using a beam of uranium ions and a magnetic field; the heavier particles were deflected less by the field as they had more kinetic energy.

Excellent and Flawless editing!!

Two things i want from this guy First is his mind or at least some of his knowledge and the second is his hair i just love it.

Bravo. Wonderful video! I absolutely love watching these!!!

You can tell he was going to do a mad scientist evil laugh at 2:35

This may sound like an overused cliche but this scientist actually makes science interesting. lol

He has a water bottle collection. he started it because he said he had one in a lecture and then decided he needed to make one, so if anyone asked to see it he would have something to show them.

this is a very interesting subject i have been studying atoms in my grade 10 science class and barely understood because my teacher rushed through , i have learned more from this professor than my school teacher :D thank you

That was fantastic, both of you. I wasn't aware one isotope was used destructively and one constructively - this has been good to know. :D

wow ! i love these videos !! really informative ! and interesting

You guys are great! Awesome video.

Sweet deal! I had no idea of how they enriched Uranium! UF6 definitely one of my favorite compounds now :P Great video!

Wow, Great Explanation! Thank You very Much!

Yeah same here. It's definitely one of the best KZread video series out there.

Uranium and other actinides (metallic form) are also pyrophoric (meaning it can oxidize easily with the air, causing sparks from the fine particles to ingite and even cause a fire.) The seperation of isotopes such as U-235 from U-238 requires a lot of energy. Many actinide isotopes are very unstable and radioactive, that they produce their own thermal radiation (heat), that they must be stored inside tungsten carbide. It has a much higher melting point than lead, and good radiation shielding.

wow you are very good at explaining that watched how it's made and another video but you make more sense

Thanks this was super cool, uranium is my favorite element on the periodic table, if I could make a request, could you talk about the superactinides?

excellent explanation helped a lot!

Wonderful explanation!

I'm curious why 235 is more radioactive than 238. What is it about the internal structure of the nucleus having 3 fewer neutrons that enables it to overcome the strong nuclear force. Is it the repulsiveness of the positrons that prevents them from being able to pack together too tightly? Is that what results in beta+ decay?

So if you have 99.3% U238 and .7% U235 in a jar, how do separate the 235 from 238? He might have said it in the video, and if he did then I missed it.

thanks for the tut!

I learned all about this in my high school chemistry class, as I grew up very close to the Goodyear Uranium Enrichment Plant in southern Ohio. Gaseous diffusion operations were shut down a few years ago, and now they've begun using centrifuge technology to enrich uranium to a non-weapons grade assay.

IIRC, there are about 3-4 talks about liquid thorium fluoride ractors at googletechtalks. But it's great you mention it, I've always wanted to know the professors' opinion about the subject. In any case, I liked watching them, it's a mix between nuclear physics and chemistry.

Superb explanation!

Excellent as usual.

very informative, thank you.

did a little research "DU counterweights have been used primarily in wide-body aircraft on rudders, outboard ailerons (wing assembly), and outboard elevators (tail assembly). Counterweights come in a variety of weights and shapes, and numerous weights and shapes are used in some aircraft. The DU counterweight can range in weight from 0.23 to 77 kg." "Some aircraft used for military and cargo also use DU The Boeing Company made helicopters using DU as a rotor tip weight prior to 1979.

This is awesome uranium is my favorite element on the periodic table

Thanks for making a video on this! I now have a way to enrich my Uranium.

Great vid, explains a lot. Can I ask you something Prof? What would you have to do with 235 after the whole process... how much less stable is it? Is it hard to handle? These are all particles right? Is it hard to get the mined uranium ready for the centrifuge and to take it out after the process? 238 is a lot less reactive? How much is a lot? Precautions in the lab? Thx!

oooooh its a looong one!!! I love them.... wow! thanks guys. much appreciated!

Thank You so much for Your instructive and AWESOME videos! :-)

A centrifuge enrichment facility only takes up the space and energy requirements of a supermarket whereas a diffusion enrichment facility takes up acres and acres of space and ridiculous amounts of electricity.

very cool video guys, I learned a lot.

Very helpful! Respect and love from pakistan for u sir.

The pic you showed in the video was the "Alpha Track Calutron at the Y-12 Plant at Oak Ridge, Tennessee from the Manhattan Project, used for uranium enrichment."ref: "Calutron"-Wikipedia using electromagnetic isotope separation. K-25 was the gaseous diffusion plant. Read about "Enriched Uranium" on Wikipedia...

This professor is brilliant!

Very Educative. Thanks!

I must say, I was very fortunate to have an interesting professor for chemistry. not quite equal with this gent, but very close.

7:51 "Clouds of radioactive UF6 pouring all over the place!!" Epic!

Thanks for explaining the enrichment process. I'm interested in nuclear science so this was good help. :3

Wow, I learned something today. Thanks

Nice explanation

I don't know why but you look really smart! I think it is because of your hair. Good informative video.

@petokyo UF6 is symmetrical, leaving no area of the molecule significantly more negatively-charged than the other. This means that the intermolecular forces between the molecules are very weak. Also, because the compound is no longer a metal, it does not have the metallic bonding that uranium has.

Actually, the Manhattan Project used electromagnetic separation in cyclotrons, as well as the gaseous diffusion method mentioned in the video. It was the magnetic windings of the cyclotrons that required the loan of nearly 15,000 tons of silver from the US Treasury.

You didnt talk about bombardment enrichment, I've read about it being done, although the process is not a far cry from a stack reactor with a central target, but I don't understand why you need to have the material in the target in a substrate, why is this? Love your videos!

Now correct me if im wrong, but i am pretty shure that the teflon was not used for ww2, that picture he showed where calutrons, huge elctomagnetic seperators. The u 238 was fed through the magnetic field and due to the different masses the 235 would be seperated, though this process was slow and required a lot of calutrons. I recently visted Oakridge and everything i saw and heard never once mentioned teflon.

man this is good stuff!! i really enjoy these videos. just a thought... maybe if he filmed in front of a green screen.. he could make the background look as if he was giving this lecture from frankenstein laboratory hehe.. now that would be pretty cool

i love the professor!

I love your videos! Have you thought about making a video about the liquid fluoride thorium reactor (LFTR)?

whats with scientists and the crazy hair?

wow... didnt know that second part... but isn't DU also used in the armor plating of tanks n such? I'm sure not it massive amounts...

Fascinating!

For any given element, there is a certain isotope(amount of neutrons) that is most stable. Going above or below this number decreases the stability of the nucleus. 238 just happens to be closer to the stable isotope (if not the most stable isotope, I'm not sure) than 235.

where can I get hold of the raw material???

yes, its sometimes used as a core to give armor piercing rounds more mass which means they can hit with more power, however it is not used as a nuclear weapon it self

Love his hair

The slower velocity is important in the diffusion method of enrichment, but this doesn't mean anything in a centrifuge. Centrifuges basically create an artificial "gravity." As you know, gravity causes heavier things to sink to the bottom and lighter things to float up top. Note the stratification of the earth itself - heavy iron is at the bottom and gases are at the top. "Bottom" in a centrifuge is near the edge, and "top" is in the center, where "gravity" (centrifugal force) is the the least.

i want this guy as my science teacher...

depleted U238 is also used for armor piercing bullets

Great Scott

yes, armor piecing bullets, bunker busters.. a projecting penetrates its target better when its mass is concentrated in a smaller place, like with uranium 238.

AAaaaah I just started with atoms and stuff today in Physical Science... time to finally make good use of these videos :D

Doesn't the U238 have a slower velocity (bigger mass) and thus stay more in the center? In the video it's explained the other way around.

Hahah I didn't notice that until I scrolled down toward the end and saw your comment!

In many cases, tungsten alloy counterweights have replaced DU counterweights in aircraft. Since 1981, The Boeing Company has provided customers with tungsten replacement counterweights, and tungsten counterweights have been installed in new Boeing 747 aircraft. Tungsten equivalents have been sent as spares since 1981It is unknown how many DU counterweights are currently installed in aircraft., the number of aircraft that contain DU counterweights is decreasing

i love that guys hair! :D

@ASAM90 Ok, I was just wondering cause they talked about how much more complicated and hard to do than it seems at first glance. --Cary

Sure there is. You can't find it just by looking at a newtonian diagram though, since it is of no real consequence. Think of centrifugal force as the impact force from the uranium unto the centrifuge wall, and you'll sort of see what I mean. I agree though, he should've said centripetal force, it's the only thing that makes sense to use :).

Brilliant.

Mucha quimica y ciencia pero no conoce que para el pelo hay una solucion que contiene llamada shampoo y sobre todo acondicionador. Lo podria usar en su pelo no?

Thanks again

@mint285e oh I am happy to know that , and thank you Dear

nice to know, tnx for the recap ;-)

Even if I had like a ton of americium? Say I took apart like 300 smoke detectors and packed it all inside the lead pipe, would that generate enough neutrons? And is there any way to direct the neutron radiation (like basically shooting it). Also, I have a lot of radium paint (struck a gold mine at an antique mall on the clocks), is it true you can use radium instead of using americium to create neutron particles?