i barely passed chemistry in high school, so i admit i'm shocked at how much time i spend watching these totally fascinating periodicvideos! great work folks!
The decay sequence is: Uranium-238 to thorium-234 to protactinium-234 to Uranium-234 to thorium-230 to radium-226 to radon-222 to polonium-218 to lead-214 to bismuth-214 to polonium-214 to lead-210 to bismuth-210 to polonium-210 to lead-206 which is its final stable form.
How did I miss this even though I've been subscribed for a year? I love to see The Professor's sense of wonder at everything from balloons in low pressure to the color of Plutonium salts.
Fantastic stuff! I love your videos. You make highly complex subjects not only accessible to the average man but you make them fun. You passion for the subject matter is infectious!!!
Wonderful lab, the colour of plutonium is certainly interesting, good to get rid of that cliché stigma about radioactive elements all being neon green haha.
Wow The Professor was so happy & excited, like he was going to see the NUCLEAR lab! :D Amazing how every new thing you learn and see in chemistry makes you feel happy like a little kid. :)
Yes. An alpha particle is just a helium nucleus with very high kinetic energy; just as a beta particle is an electron (or positron) with high kinetic energy. However, the names alpha and beta are only used when the particles get ejected from a nucleus. If a gamma ray hits an electron in an atom, the gamma ray may disappear, and its energy will go into kinetic energy of the electron (the photoelectric effect), which then flys off. This electron is not a beta as it didn't come from the nucleus.
I was asking myself the same question. The only explaination i can think of is this one: If you have to deal with chemicals that are not dangerous per se, but dirt from the lab would disturb your reaction. Then a positive glove box would be a good way to protect your experiment.
I have recently been thinking about the properties of catalysts and was wondering if you could do a video on how a catalysts specifically functions and how to predict whether or not a certain compound will act as a catalyst in a reaction. Basically, I am curious about whether or not there is a correlation between the properties of a reaction and the properties of the catalyst being used. Please make a video on this.
It astound me every time i hear about nuclear waste containing a good amount of 239 Pu to be stored and locked away. Im really not into conspiracy things and I have a very mitigated oppinion upon nuclear energy, but let me be really sceptical about good intentions prevail on bad ones... Dont misunderstand me... Im not Telling doc is a liar, I respect him and love periodic videos. I cant wait to see whats next... Continue your good work ;-)
I agree with you, mannonc, that hydrogen is presently best viewed as a fuel, not an energy source. But I note that chemically the situation isn't so clear cut: turning methane into hydrogen could ideally take a little less then 15% the energy made available by turning the resulting hydrogen into water. The carbon could hopefully be captured as graphite and buried.
The steam may be considered visual or sight pollution in some cases. There often are methods employed to prevent the steam condensing at the top and forming visible clouds.
Am I the only one who thinks this is a young Professor Hubert J Farnsworth (Futurama) ? Love these videos, chem study is behind me now but I watched these videos out of pure fascination! He should definitely have his own TV show.
Is there a visitors Centre for anyone to visit there? I have always dreamed of going to a nuclear Power station! I am fascinated by Ionising Radioactivity
Oh you can, its just extraordinarily difficult and the forces required to compress plutonium are huge so the explosive detonator would produce more blast than the nuclear blast
They do, but even the best geiger counters can only tell you if something is radioactive, and not what is causing the radiation. For this the tool of choice is the Scintillation Dectector, which actually determines what element is giving off the radiation. This lets it differentiate for example between the K-40 naturally in your body and some Th-232 you really shouldn't have gotten your hands into!
They are likely forced to use a certain version of windows that the drivers and the software for the spectrometer work with. Many industrial applications still run on win 3.11 because the software was designed to run on it.
That's a common misconception, U238 can definitely sustain fission, with one requirement, that the neutrons remain unmoderated. Such reactors are called "fast" as opposed to "thermal" because the neutrons whizz around at the same speed as they were released when fission occurred. Such reactors allow for the complete use of existing uranium reserves and waste products are minimal thanks to the fast neutrons. If necessary, these reactors can also use Th :) Cheap clean energy for everyone forever!
It's one of the idea they had. Drilling into the crust and injecting pressurized waste into the mantle. However, they also know there would be a risk of radioactive volcanic eruption. Like a normal volcanic eruption isn't deadly enough, make it spurt radioactive lava and ashes.
DOCTOR STRANGELOVE IS REAL !!!!!!!!!!!!!!!!!!!!! O_O !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! AAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH !!!
People have considered this, but what about using U238? We already have tons of it lying around and all we have to do is chuck it into an integral fast reactor. I think fast reactors are the ultimate nuclear reactors. Don't get me wrong, thorium is just fine, but I believe that once we perfect fast reactor technology using U238 will be much more profitable than using thorium because it's already in ceramic pellets and doesn't have to be mined.
There's an article in a recent New Scientist about using a small particle accelerator to fire a neutron beam at nuclear waste to accelerate its decay & burn it up. Apparently, this process would generate enough energy to power the accelerator and also an excess. I hope someone manages to make this work.
Radioactive stuff is't used only for energy and bombs. When they had to shut down the reactor at Chalk River, Ontario, it caused a world-wide crisis, because the reactor accounted for 40% of the world's medical isotopes production. medical isotopes can't be stored at all because they have extremely short half-life, the primary characteristic that make them useful for medicine.
If you have some thing that is radioactive you may wear a : Hazmat Suit, Mask ( One with holes ) and some pair of gloves - You must wear them all times if you see some thing radioactive. Please move any living thing from any non-stored things that are radioactive. :3
Chemistry is such a fascinating realm in it's own right to be fair but being a scientist is much more than knowing the facts. To be a scientist, you must question everything and accept nothing. Only by doing things yourself can you really understand everything and performing even basic experiments, it really helps you view the universe in a whole new perspective. Seeing really is believing :)
This is more of a Physics question than a Chemistry question, but: can the effects of alpha and beta particles be obtained by simply creating an electric field that accelerates helium nuclei or electrons? For example, by using an ionizer to ionize helium and accelerate the obtained He++ ions, and by using a Lenard tube to fire out electrons. If it can't be done, why? What makes alpha and beta particles different than simple helium nuclei or electrons moving at high speed, except their origin?
Yellowcake still the bestlooking. - Nuclear power still the best. It will break down to lead or smaller eventually, so best to take advantage of it, accelerate the process if necessary, no CO2 clouds.
Depends on your perspective. If you live on the mainland of a major continent then the UK is pretty small by comparison to that. Here in the US just the State of Texas is 696,241 square kilometers which is ~2.85 times the area of the entire UK and that's just the State I live in. Where I grew up if you wanted to go to the theater you had to drive at least 45 minutes to a bigger town that had one. ;p We didn't consider it a long drive.
The kid had his hand in the nuclear waste drum? Reminds me of a kid in my class in high school. We were being shown a beaker of hydrochloric acid and we were told it was corrosive, but we were also told it generated heat and to touch the bottom of the beaker... And this kid stuck his finger in the beaker itself.
"It's a very nice demonstration to somebody like me whos been a safety officer of just how carefully you have to work with radioactive materials." Just as he finished talking about keeping your hands in your pocket while he flailed his arms around like a typhoon.
Good point! I don't think we can solve all of our energy needs that way, but it would be a helpful supplement and could provide a cheaper and cleaner way of generating hydrogen for use as a fuel.
Thorium isn't less efficient than plutonium production - it's just less efficient than the simple fission of U-235. Thorium-232 has a much larger capture cross section than uranium-238. U-233 thermal fission does produce fewer neutrons than Pu-238 fast fission - that distinction leading to the research preference for the IFR. The gammas from U-232 contamination is a benefit, in my opinion; it offers proliferation resistance, since it's harder to handle - but can be automated without a problem.
/agree I live in Texas. A long drive is something VERY different for me. 5 hours just to get back to my hometown and that's not even halfway across the State. ;p
If it isn't hooked up to the 'net, doesn't have open USB ports (I know. Win95 doesn't have USB. It's just the idea), isn't part of a mission critical item, and is fully formatted and reinstalled every month, I don't see the problem. Even a Linux/Unix system in a mission critical application is normally wiped and reinstalled every now and then.
Indeed it is. It tastes like a bullion-cube with the consistency of earwax. If would in fact be improved by adding some nuclear material to the mix, at best something emitting alpha particles. That would give sufficient reason not to eat the stuff.
Hmmm.... the 'contamination' the Professor mentioned... if it's not possible to scrub the equipment and decontaminate it, wouldn't that severely complicate the chemistry being done? I'm always curious about purity in chemistry... it seems many reactions are quite tolerant to impurities, but I would expect purity to be extremely important in research settings. Do they have to go to pains to track the history of equipment to accurately record all chemicals involved in each experiment?
Oh, okay, lol. I thought you are saying the some linux have better securities than others. lol I have ubuntu installed on another partition, and you are definitely right about the ease of installation process.
Personally before I thought of radioactive as a radiation (i.e. non contact thing) and I feared it, because it could make other things radioactive and you wouldn't feel it. Now that I learn more and more about radioactive materials I'm less and less afraid of it. Mostly due to the fact that some radiation can be treated with merely washing your hands.
You are incorrect in thinking lead starts as uranium. Also, when most isotopes decay, they arent potentially lethal. So thats why people are a bit upset about radioactive waste.
Not quite right. Thorium isn't fissile. If irradiated in a nuclear reactor, then it can be converted into uranium (like U238 is converted to Pu239) in a regular reactor. But the process of thorium irradiation is much less efficient and much more complicated. Additionally, the uranium produced by thorium irradiation (U233) is exceedingly radioactive and produces very strong gamma rays (by contrast plutonium is mildly radioactive and produces weak gamma) making very difficult to handle.
I want to see a video where each member of the Periodic Videos tell us their favorite nerdy pick-up line. Example: "Hey! Are you an alpha carbon? Cuz you look susceptible to a backside attack."
Fusion is the bomb! ;) I rather see more work be put into that, though I can't say I know to much on the technical benefits of having one kind of project or the other, though I know the energy released through fusion is much better. Waste isn't exactly the issue at that point. I wonder if fusion could replace fission or are they both useful? My mind set is that one is just more primitive and out dated compared to the other, I'm very option to correction/ explanation though.
Honestly, after what happened in Fukushima, I don't trust the safety of any nuclear facility, much less the reactors. How dangerous would thorium be? How radioactive? Would it be have to be stored for all that time securely?
Sooo uh.... what happened to that kid with his arms in the radioactive drum?
i barely passed chemistry in high school, so i admit i'm shocked at how much time i spend watching these totally fascinating periodicvideos! great work folks!
"I'm not allowed to tell you where we're going" Description: We're at Sellafield
The decay sequence is:
Uranium-238 to thorium-234 to protactinium-234 to Uranium-234 to thorium-230 to radium-226 to radon-222 to polonium-218 to lead-214 to bismuth-214 to polonium-214 to lead-210 to bismuth-210 to polonium-210 to lead-206 which is its final stable form.
well, he kept his hands in his pockets for about ... 10 seconds :D
1:30 So Brady basically invented "WHAT ARE THOSE?!" like three years ago.
Those are some nice shoes, professor.
Why not discuss the shoes?
At 0:29, I thought "Oh no, don't look at the map, put your hands on the wheel professor! Oh right, this is Britain.
So if Steve, the "radioactive expert" bites you, do you gain the proportional strength of an expert?
I am positively surprised to see this renewed focus on nuclear chemistry. Thanks periodic videos!
4:03 You said you have to keep your hands in the pockets
How did I miss this even though I've been subscribed for a year? I love to see The Professor's sense of wonder at everything from balloons in low pressure to the color of Plutonium salts.
This is sooo awesome! I'm getting my Ph.D. in nuclear chemistry :)
Prof. Poliakoff sure is smart.
Martyn's hair doesn't just happen. Can you please do a video on how he keeps it so damn awesome?
This has been the highlight of my day. Can't wait for the updated element videos.
If that man was my connection to chemistry in the first place I would be a chemist :P
Fantastic stuff! I love your videos. You make highly complex subjects not only accessible to the average man but you make them fun. You passion for the subject matter is infectious!!!
Beautiful just beautiful, I would love to see what goes on there.
Wonderful lab, the colour of plutonium is certainly interesting, good to get rid of that cliché stigma about radioactive elements all being neon green haha.
"it's hard for me to keep my hands in my pocket"
2 seconds later...
"So you have to think of your experiments enormously more careful than..."
Goes back to lab in Nothingham...
Boom!
That childhood visit to a nuclear facility must explain the professor's eye-catching hair style!
;-)
Wow The Professor was so happy & excited, like he was going to see the NUCLEAR lab! :D Amazing how every new thing you learn and see in chemistry makes you feel happy like a little kid. :)
I love how the professor is always using his hands when speaking
0:08 You don't even have to tell us. The title of the video gives it away.
The Professor's hand gestures excites me just as much as the content of chemistry.
it was a joke. the boy didnt follow the "hands in pockets" rule so they sarcastically put his hands in a drum labeled radioactive waste.
No, professor's hair undergoes nuclear decay and still emits radioactive particles.
Yes. An alpha particle is just a helium nucleus with very high kinetic energy; just as a beta particle is an electron (or positron) with high kinetic energy.
However, the names alpha and beta are only used when the particles get ejected from a nucleus.
If a gamma ray hits an electron in an atom, the gamma ray may disappear, and its energy will go into kinetic energy of the electron (the photoelectric effect), which then flys off. This electron is not a beta as it didn't come from the nucleus.
PARTY IN THE GLOVE BOX
This Professor is one of the most sympathetic people i've ever seen. He's what you would call so "cute". I'm male by the way.
I was asking myself the same question. The only explaination i can think of is this one: If you have to deal with chemicals that are not dangerous per se, but dirt from the lab would disturb your reaction. Then a positive glove box would be a good way to protect your experiment.
I still can't wait for your new Thorium video. I hope you get to look into LFTR when you do it!
I have recently been thinking about the properties of catalysts and was wondering if you could do a video on how a catalysts specifically functions and how to predict whether or not a certain compound will act as a catalyst in a reaction. Basically, I am curious about whether or not there is a correlation between the properties of a reaction and the properties of the catalyst being used. Please make a video on this.
There's a party in my glovebox and you're all invited.
It astound me every time i hear about nuclear waste containing a good amount of 239 Pu to be stored and locked away. Im really not into conspiracy things and I have a very mitigated oppinion upon nuclear energy, but let me be really sceptical about good intentions prevail on bad ones...
Dont misunderstand me... Im not Telling doc is a liar, I respect him and love periodic videos. I cant wait to see whats next... Continue your good work ;-)
Is that a .... periodic table tie? :D
I couldn't do "hands in the pockets" and still talk about things. I admire you, professor.
the thing that amazed me is that you hadnt seen radioactive stuff before , your a prof shorly you have
these videos really make me want to be a chemist but im already 2 years deep into an engineering degree lol oh well maybe a science minor?
I agree with you, mannonc, that hydrogen is presently best viewed as a fuel, not an energy source. But I note that chemically the situation isn't so clear cut: turning methane into hydrogen could ideally take a little less then 15% the energy made available by turning the resulting hydrogen into water. The carbon could hopefully be captured as graphite and buried.
Thx for posting this, great videos as always!
The steam may be considered visual or sight pollution in some cases. There often are methods employed to prevent the steam condensing at the top and forming visible clouds.
Am I the only one who thinks this is a young Professor Hubert J Farnsworth (Futurama) ?
Love these videos, chem study is behind me now but I watched these videos out of pure fascination! He should definitely have his own TV show.
Is there a visitors Centre for anyone to visit there? I have always dreamed of going to a nuclear Power station! I am fascinated by Ionising Radioactivity
Oh you can, its just extraordinarily difficult and the forces required to compress plutonium are huge so the explosive detonator would produce more blast than the nuclear blast
THANKS PROFESSOR
They do, but even the best geiger counters can only tell you if something is radioactive, and not what is causing the radiation. For this the tool of choice is the Scintillation Dectector, which actually determines what element is giving off the radiation. This lets it differentiate for example between the K-40 naturally in your body and some Th-232 you really shouldn't have gotten your hands into!
Comparing radioactivity to Marmite! That just made my day. Now I'm even more keen to try it.
In my opinion thorium reactors are the future
They are likely forced to use a certain version of windows that the drivers and the software for the spectrometer work with.
Many industrial applications still run on win 3.11 because the software was designed to run on it.
That's a common misconception, U238 can definitely sustain fission, with one requirement, that the neutrons remain unmoderated. Such reactors are called "fast" as opposed to "thermal" because the neutrons whizz around at the same speed as they were released when fission occurred. Such reactors allow for the complete use of existing uranium reserves and waste products are minimal thanks to the fast neutrons. If necessary, these reactors can also use Th :)
Cheap clean energy for everyone forever!
The professor's mysterious secret shoes...
It's one of the idea they had. Drilling into the crust and injecting pressurized waste into the mantle. However, they also know there would be a risk of radioactive volcanic eruption. Like a normal volcanic eruption isn't deadly enough, make it spurt radioactive lava and ashes.
I one visited an uranium enrichment factory in Almelo, Holland. Never been through so much security measures.
DOCTOR STRANGELOVE IS REAL !!!!!!!!!!!!!!!!!!!!!
O_O !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
AAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH !!!
Yeah, he did NOT say it was an alien UFO, yet you're correcting him on it.
THAT'S EXACTLY THE POINT I WAS MAKING.
lol awesome video, love the story at the end lol! cant wait for those next elements.
People have considered this, but what about using U238? We already have tons of it lying around and all we have to do is chuck it into an integral fast reactor. I think fast reactors are the ultimate nuclear reactors. Don't get me wrong, thorium is just fine, but I believe that once we perfect fast reactor technology using U238 will be much more profitable than using thorium because it's already in ceramic pellets and doesn't have to be mined.
I hope he could be my professor of Chemistry, of Math or any type of natural science!
There's an article in a recent New Scientist about using a small particle accelerator to fire a neutron beam at nuclear waste to accelerate its decay & burn it up. Apparently, this process would generate enough energy to power the accelerator and also an excess. I hope someone manages to make this work.
There is plenty of uranium around and there are various complications with thorium that making switching over not worth it at the present time.
Radioactive stuff is't used only for energy and bombs. When they had to shut down the reactor at Chalk River, Ontario, it caused a world-wide crisis, because the reactor accounted for 40% of the world's medical isotopes production. medical isotopes can't be stored at all because they have extremely short half-life, the primary characteristic that make them useful for medicine.
If you have some thing that is radioactive you may wear a : Hazmat Suit, Mask ( One with holes ) and some pair of gloves - You must wear them all times if you see some thing radioactive. Please move any living thing from any non-stored things that are radioactive.
:3
Chemistry is such a fascinating realm in it's own right to be fair but being a scientist is much more than knowing the facts.
To be a scientist, you must question everything and accept nothing. Only by doing things yourself can you really understand everything and performing even basic experiments, it really helps you view the universe in a whole new perspective.
Seeing really is believing :)
This is more of a Physics question than a Chemistry question, but: can the effects of alpha and beta particles be obtained by simply creating an electric field that accelerates helium nuclei or electrons? For example, by using an ionizer to ionize helium and accelerate the obtained He++ ions, and by using a Lenard tube to fire out electrons.
If it can't be done, why? What makes alpha and beta particles different than simple helium nuclei or electrons moving at high speed, except their origin?
hahahaha the professor never fails to crack me up !
Yellowcake still the bestlooking.
-
Nuclear power still the best. It will break down to lead or smaller eventually, so best to take advantage of it, accelerate the process if necessary, no CO2 clouds.
Wouldn't it be funny if he'd come out of the lab all bald, saying "oh my... what an exiting day that was!"...
Can you do a video showing that Plutonium 241 pellet inside a cloud chamber? I bet it would look amazing.
Depends on your perspective. If you live on the mainland of a major continent then the UK is pretty small by comparison to that. Here in the US just the State of Texas is 696,241 square kilometers which is ~2.85 times the area of the entire UK and that's just the State I live in. Where I grew up if you wanted to go to the theater you had to drive at least 45 minutes to a bigger town that had one. ;p We didn't consider it a long drive.
The kid had his hand in the nuclear waste drum? Reminds me of a kid in my class in high school. We were being shown a beaker of hydrochloric acid and we were told it was corrosive, but we were also told it generated heat and to touch the bottom of the beaker... And this kid stuck his finger in the beaker itself.
Thank you for enlightening me... again. looking forward to the new Plutonium vid.
"It's a very nice demonstration to somebody like me whos been a safety officer of just how carefully you have to work with radioactive materials." Just as he finished talking about keeping your hands in your pocket while he flailed his arms around like a typhoon.
This video is awesome! One of the best yet!
Finally we see some real plutonium!
Good point! I don't think we can solve all of our energy needs that way, but it would be a helpful supplement and could provide a cheaper and cleaner way of generating hydrogen for use as a fuel.
They did. They used planes with cameras. Took pictures and made maps based on those pictures. I'm not saying that's how all maps were made, just some.
Thorium isn't less efficient than plutonium production - it's just less efficient than the simple fission of U-235. Thorium-232 has a much larger capture cross section than uranium-238. U-233 thermal fission does produce fewer neutrons than Pu-238 fast fission - that distinction leading to the research preference for the IFR.
The gammas from U-232 contamination is a benefit, in my opinion; it offers proliferation resistance, since it's harder to handle - but can be automated without a problem.
He was probably the boy with his hands in the waste, that's why they have a mind of their own.
Can't wait for the new videos!
I see the professor likes video games. No other reason to use a map than the feeling of being on a quest
/agree I live in Texas. A long drive is something VERY different for me. 5 hours just to get back to my hometown and that's not even halfway across the State. ;p
Good News Everybody
Not in the general case, because of the concept of critical mass. The surface to volume ratio must be smaller.
If it isn't hooked up to the 'net, doesn't have open USB ports (I know. Win95 doesn't have USB. It's just the idea), isn't part of a mission critical item, and is fully formatted and reinstalled every month, I don't see the problem. Even a Linux/Unix system in a mission critical application is normally wiped and reinstalled every now and then.
Indeed it is. It tastes like a bullion-cube with the consistency of earwax. If would in fact be improved by adding some nuclear material to the mix, at best something emitting alpha particles. That would give sufficient reason not to eat the stuff.
Hmmm.... the 'contamination' the Professor mentioned... if it's not possible to scrub the equipment and decontaminate it, wouldn't that severely complicate the chemistry being done? I'm always curious about purity in chemistry... it seems many reactions are quite tolerant to impurities, but I would expect purity to be extremely important in research settings. Do they have to go to pains to track the history of equipment to accurately record all chemicals involved in each experiment?
Oh, okay, lol. I thought you are saying the some linux have better securities than others. lol I have ubuntu installed on another partition, and you are definitely right about the ease of installation process.
thanks for the tour!
Personally before I thought of radioactive as a radiation (i.e. non contact thing) and I feared it, because it could make other things radioactive and you wouldn't feel it.
Now that I learn more and more about radioactive materials I'm less and less afraid of it.
Mostly due to the fact that some radiation can be treated with merely washing your hands.
You are incorrect in thinking lead starts as uranium.
Also, when most isotopes decay, they arent potentially lethal. So thats why people are a bit upset about radioactive waste.
You guys should do a video about the 2 new elements :)
Not quite right. Thorium isn't fissile. If irradiated in a nuclear reactor, then it can be converted into uranium (like U238 is converted to Pu239) in a regular reactor. But the process of thorium irradiation is much less efficient and much more complicated.
Additionally, the uranium produced by thorium irradiation (U233) is exceedingly radioactive and produces very strong gamma rays (by contrast plutonium is mildly radioactive and produces weak gamma) making very difficult to handle.
I remember visiting the nuclear visitors senter in wales when i was really young. in 2008 i visited chernobyl and pripyat
highly recommended
I want to see a video where each member of the Periodic Videos tell us their favorite nerdy pick-up line. Example: "Hey! Are you an alpha carbon? Cuz you look susceptible to a backside attack."
Fusion is the bomb!
;) I rather see more work be put into that, though I can't say I know to much on the technical benefits of having one kind of project or the other, though I know the energy released through fusion is much better. Waste isn't exactly the issue at that point. I wonder if fusion could replace fission or are they both useful? My mind set is that one is just more primitive and out dated compared to the other, I'm very option to correction/ explanation though.
Honestly, after what happened in Fukushima, I don't trust the safety of any nuclear facility, much less the reactors.
How dangerous would thorium be? How radioactive? Would it be have to be stored for all that time securely?