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Anatharon posted:That somehow weirds me out even more then Webdog's thing. How does that work? Botox is botulism toxin. hallo spacedog posted:For about 5 years I was terrified to eat anything from cans because my bio teacher in HS told us about someone who had a can that was infected with botulinuum, took one taste of the contents and dropped dead on the spot. Well, that's certainly a very exaggerated story. It takes a while for botulism to kill you. You first get symptoms hours or even days after exposure. And most preserves are relatively safe. C. Botulimium hates acidic environments, and most preserves have enough acid to kill any spores. It's when you get into canning/preserving of low-acid foods (like meats, non-pickled vegetables, etc...) that the risk rises, which is why botulism was much more prevalent in the late 19th/early 20th centuries when canning technology was still in its infancy. DrBouvenstein has a new favorite as of 21:41 on Jan 13, 2014 |
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Jan 13, 2014 21:39
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Anatharon posted:That somehow weirds me out even more then Webdog's thing. How does that work? Botulinum toxin is a nerve poison. So step 1 is to dilute the gently caress out of it, and step 2 is to inject it into the face. It paralyses the nerves, causing the muscles they control to relax and the wrinkles to disappear (and leaving you with a permanently blank expression because some of your facial muscles don't work anymore).
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Jan 13, 2014 21:51
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Skeesix posted:Has anyone figured out what exactly is going on there? It's gotta be some reaction, right? The Lone Badger posted:Botulinum toxin is a nerve poison. So step 1 is to dilute the gently caress out of it, and step 2 is to inject it into the face. It paralyses the nerves, causing the muscles they control to relax and the wrinkles to disappear (and leaving you with a permanently blank expression because some of your facial muscles don't work anymore).   
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Jan 13, 2014 21:51
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DrBouvenstein posted:Well, that's certainly a very exaggerated story. It takes a while for botulism to kill you. You first get symptoms hours or even days after exposure. Yeah, I know it's silly and ridiculous fear (and also that she was pretty much lying about the dropping dead thing,) stuff like that just gets under my skin. Maybe one day I will try it though.
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Jan 13, 2014 21:56
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Azido azideazide has excited a research laboratory specialising in explosive, high-nitrogen compounds. This is mostly because they detonated infrared spectrometers when they tried to measure it. When they finally got the light source to a level so low they wouldn't blow up the spectrometer, the spectrum was pretty bad. Their X-ray crystallography was apparently very good, though. N-amino azidotetrazole is our starting material. Fellow chemists in the audience, I apologise for the heart attack for having to read "azidotetrazole" and the realisation that you can make something bigger and nastier from it.
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Jan 13, 2014 22:09
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Explosive organic chemistry: let's see how many nitrogen we can cram onto a molecule without losing limbs! Remember kids, it's a jump off a tall, tall cliff from organic nitrogen to N2 gas.
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Jan 13, 2014 22:32
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GWBBQ posted:My first impression was the same as Jamie's - a steam explosion aerosolizes the thermite and it burns very rapidly. I like that idea. The way to test it would be to put the thermite on top of dry ice. It still produces a gas powderizing the thermite but doesn't have the H2O -> H2 + 0.5O2 that could also happen.
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Jan 13, 2014 23:25
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Botulinum toxin and Botox are classic examples of the basic dose-response principle of toxicology, and I usually cite them when explaining toxicology in general. Sure, it's the most potent toxin known to humanity, but at a proper dose it's fairly harmless (though, perhaps not aesthetically harmless). It should be noted that Botox is used for more than hideous plastic surgery. As noted earlier, Botox is a nerve poison which paralyzes muscles by preventing the release of acetylcholine from the synapses of cholinergic neurons. This has been shown to be usefully therapeutic in cases of nerve dysfunction in the head and neck area. PubMed has a fairly good review here.
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Jan 13, 2014 23:26
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Intoluene posted:Azido azideazide has excited a research laboratory specialising in explosive, high-nitrogen compounds. This is mostly because they detonated infrared spectrometers when they tried to measure it. When they finally got the light source to a level so low they wouldn't blow up the spectrometer, the spectrum was pretty bad. Their X-ray crystallography was apparently very good, though. This might be the third or fourth time this has been mentioned in this thread, I'm not sure, but still, it kicks rear end. Those guys are loving nuts and I salute them for it.
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Jan 14, 2014 00:29
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KozmoNaut posted:Some dude near where my parents live had like 250 liters of ether in his basement, from when he used to fly model airplanes. After a news segment on TV concerning the dangers of stored ether in school laboratories, he phoned the local fire department and asked them what he should do with 250 liters of potentially very unstable ether. Their response was "Sleep somewhere else tonight, the bomb disposal unit will be there first thing in the morning". And to think, I was worried about a half liter bottle of the stuff. I should have just huffed it to see if Thompson was right. Let me contribute Fluoroantimonic acid, a super-acid ten quadrillion times stronger than 100% sulfuric acid. It also reacts violently (explosively) with water, producing hydrogen fluoride gas.
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Jan 14, 2014 01:18
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Ordinaire posted:Botulinum toxin and Botox are classic examples of the basic dose-response principle of toxicology, and I usually cite them when explaining toxicology in general. Sure, it's the most potent toxin known to humanity, but at a proper dose it's fairly harmless (though, perhaps not aesthetically harmless). Its also used for patients with range of motion issues following car accidents and other traumatic injuries. Relaxes muscles so physical therapy can work to build strength and flexibility, and means less oral muscle relaxers to prevent chronic pain.
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Jan 14, 2014 01:21
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Say Nothing posted:"There is nothing more helpless and irresponsible than a man in the depths of an ether binge." - Hunter S. Thompson The wiki page just had me going NOPE NOPE NOPE NOPE all the way through. That stuff sounds horrific.
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Jan 14, 2014 01:38
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That reminds me of another wonderful substance with "hexaflouride" in its name: Uranium Hexaflouride Used in the process of enriching uranium, it too is horribly corrosive, toxic and reacts "vigorously" with water to produce HF. So much so the fact that it's also radioactive is more of an afterthought on all the safety information about the stuff.
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Jan 14, 2014 02:06
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GWBBQ posted:Hydrofluoric Acid I was unaware of this.   
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Jan 14, 2014 02:14
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I assume it's because the sulfur hexafluoride gets broken down into HF and something else, probably sulfuric acid or sulfur oxides, which then become sulfuric acid? Been a while since I took chemistry, but...
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Jan 14, 2014 02:17
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Previa_fun posted:Dimethyl mercury is pretty loving It gets better, dimethyl mercury is the internal reference for 199Hg NMR. Only a madman would think that would be a good choice.In fact several of the recommended NMR standards are terrible. 19F uses CFCl3, which kills the ozone and as I can attest is almost impossible to work with. TMS isn't that good for you either but 99% of the solvent NMR is done with has it. Stripnyme is used as an instrument calibration standard. And solvents can be bad but only if you pretty stupid. D2O is amusing since it makes ice cubes that sink in normal water, but ingestion would be fatal.
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Jan 14, 2014 02:42
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Ezekiel_980 posted:D2O is amusing since it makes ice cubes that sink in normal water, but ingestion would be fatal. D2O actually isn't as toxic as everybody thinks it is. It would take you chugging a few litres of it to actually cause any sort of ill effects. http://en.wikipedia.org/wiki/Heavy_water#Toxicity_in_humans For my contribution, diazomethane is always fun to work with. It has historically required extremely specialized glassware to work with, because friction of this gas with the standard glassware joints (which consist of ground glass) is enough to cause surprisingly large explosions. As with any gas, it's not easy to work with in general, but it being hilariously explosive and extremely toxic, both acutely and most likely very carcinogenic in the long term, make it pretty scary. In organic synthesis, it's likely the simplest method for transforming a carboxylic acid into a methyl ester. Because it's so reactive, it works in a matter of seconds/minutes in very high conversions, and because it's a gas, it doesn't require much purification, as the excess just evaporates out of your reaction mixture. I remember being seriously freaked out when I had to use it for part of my undergraduate thesis project at first, but by the time you've used it a couple of dozen times, working with thirty grams of super toxic, extremely explosive, bright yellow gas is not as scary as it probably should be.
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Jan 14, 2014 02:57
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This thread makes me regret doing my undergrad in chemical engineering to a point, simply because I want to gently caress about directly with all this dangerous poo poo  Designing a chlorinated methanes plant (that no one will ever build) just isn't as appealing as synthesising the stuff with my own hands.
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Jan 14, 2014 03:24
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kastein posted:This might be the third or fourth time this has been mentioned in this thread, I'm not sure, but still, it kicks rear end. I hadn't seen it in the current thread so it may have been posted in one before now. Either way, it deserves all these mentions. Klapötke are crazy, crazy people and deserve some kind of award for all the work they're putting in to chemicals that go boom when you breathe on them from across the room.
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Jan 14, 2014 05:37
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Now that I think about it you are probably right. And I've read In The Pipeline several times over, so it probably felt like it had been mentioned more... They are nuts. The kind of nuts I would pay good money to watch - from a very healthy distance.
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Jan 14, 2014 05:55
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DrBouvenstein posted:And most preserves are relatively safe. C. Botulimium hates acidic environments, and most preserves have enough acid to kill any spores. Clostridium Botulinum is a lovely little microbe. It * Is common and widespead * Forms spores (meaning that even if you kill it off via normal cooking it will emerge zombie-like as soon as the food cools down) * Is a psychrophile (meaning it can grow under refrigeration, albeit slowly) * Prefers to grow in the absence of air, like the inside of preserving containers * Has no obvious effect on the food's appearance / odour * Produces one of the most lethal neurotoxins known to man. Furthermore even if you properly reheat your food and kill off all the bacteria the poison is still there and will still kill you. Fortunately it does not like acid at all. It will not grow at all below pH 4.5. So acidic preserves are safe. If you're making a non-acid preserve then you need to use thoroughly excessive amounts of cooking (after you seal the container) to destroy even the memory of s surviving spore. The industry standard method is to use a pressurised retort to heat to 121 degrees C for 2.4 minutes. This is the equivalent of boiling for over seven hours.
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Jan 14, 2014 07:45
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Edit: I just noticed the chemical I was chatting about, chlorine trifluoride was mentioned in the first post! D'oh! It's worth mentioning this page again. Things I Won't Work With A great source of dangerous and weird chemicals. Say Nothing has a new favorite as of 09:05 on Jan 14, 2014 |
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Jan 14, 2014 09:03
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Say Nothing posted:It's worth mentioning this page again. That site is great but the overabundance of commas makes it really hard to read. What is it about nitrogen pairs that makes Azidoazide Azides explosive?
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Jan 14, 2014 14:09
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Ak Gara posted:What is it about nitrogen pairs that makes Azidoazide Azides explosive? From my limited understanding the nitrogen in the azides have so much energy in the bonds that they need very little encouragement to collapse and form N2 gas is a hurry.
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Jan 14, 2014 14:18
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Ak Gara posted:That site is great but the overabundance of commas makes it really hard to read. Basically, it comes down to bond energies. Nitrogen gas (N2) has very little energy in the bond between the atoms. Bonding nitrogens together in large numbers (azidoazide azide blah blah blah stuff as many nitrogens as we can into as little space as possible with as few carbons and hydrogens around to keep them sane as we can manage, ohhh cool the fume hood exploded, etc) involves lots of high energy double and triple bonds as well as a lot of funky bond angles that basically put stress on the connection in the first place. So once something (which isn't usually much) bumps the molecule enough to give it the little bit of energy it needs to get started, it simply collapses and all the breaking double/triple/stressed bonds release a fuckton of energy while the N2 gas produced uses very little energy in forming its molecules. Result: a LOT of energy is released and something that was a single molecule in a solid or liquid (say, C2N14) has suddenly become a couple of carbons sitting around while seven N2 molecules head for the hills. That kind of "one molecule turns into seven plus a little leftover stuff when you look at it funny" reaction that requires no real chemical input and very little mechanical trigger is something you want to be very careful around. It's like a house of cards, effectively. Except the cards go off like firecrackers and each turn into seven or eight cards when the whole thing comes crashing down. kastein has a new favorite as of 15:46 on Jan 14, 2014 |
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Jan 14, 2014 14:58
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The Lone Badger posted:Fortunately it does not like acid at all. It will not grow at all below pH 4.5. So acidic preserves are safe. In addition, even if you consume some live bacteria or its spores, as long as it hasn't had time to reproduce and make its toxin before you eat it, you should be safe, since your stomach acid will kill it and the spores. This, incidentally, is why you should NEVER feed honey to infants under 1 year old. Th combination of weak stomach acid and an under-developed gut flora means the spores can colonize and go to town. And honey is often chock full of botulism spores. quote:Infant botulism results from the ingestion of the C. botulinum spores, and subsequent colonization of the small intestine. The infant gut may be colonized when the composition of the intestinal microflora (normal flora) is insufficient to competitively inhibit the growth of C. botulinum and levels of bile acids (which normally inhibit clostridial growth) are lower than later in life.
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Jan 14, 2014 15:47
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kastein posted:Basically, it comes down to bond energies. Nitrogen gas (N2) has very little energy in the bond between the atoms. Bonding nitrogens together in large numbers (azidoazide azide blah blah blah stuff as many nitrogens as we can into as little space as possible with as few carbons and hydrogens around to keep them sane as we can manage, ohhh cool the fume hood exploded, etc) involves lots of high energy double and triple bonds as well as a lot of funky bond angles that basically put stress on the connection in the first place. So once something (which isn't usually much) bumps the molecule enough to give it the little bit of energy it needs to get started, it simply collapses and all the breaking double/triple/stressed bonds release a fuckton of energy while the N2 gas produced uses very little energy in forming its molecules. Result: a LOT of energy is released and something that was a single molecule in a solid or liquid (say, C2N14) has suddenly become a couple of carbons sitting around while seven N2 molecules head for the hills. That kind of "one molecule turns into seven plus a little leftover stuff when you look at it funny" reaction that requires no real chemical input and very little mechanical trigger is something you want to be very careful around. And obviously, those 7 N2 molecules want to occupy rather a lot more space than the original molecule did. I'd liken it to some arcane clockwork made up of mostly compressed springs precariously balanced against each other. 
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Jan 14, 2014 15:56
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My next question then is why do 7 N2 molecules take up more room than 1 N14 molecule? I would have thought it would take up the same amount of space.
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Jan 14, 2014 15:59
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The 7 N2 molecules are a gas, while the C2N14 molecule is a (very unstable) solid. Basically the same principle as gunpowder, except it goes off without anyone doing anything to it. e: put another way, the energy contained in gunpowder is around 3 megajoules per kilogram. The energy released by C2N14 decomposing is 357 kcal/mol, which (given that a mole of C2N14 weighs 220 grams) works out to 6.79 megajoules per kilogram. It's literally twice as energy dense as gunpowder, and that's not taking into account the differing number of gas molecules produced by each, which I might take a look at in a bit. Also, the fact that it goes off if you shine dim IR light on it or touch it in any way, while gunpowder can almost be slammed on with a mallet unless there are sparks or fire involved. kastein has a new favorite as of 16:19 on Jan 14, 2014 |
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Jan 14, 2014 16:12
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Ak Gara posted:My next question then is why do 7 N2 molecules take up more room than 1 N14 molecule? I would have thought it would take up the same amount of space. If I remember any chemistry correctly, it's because without the bond forcing them to be near each other they don't want to be anywhere near each other. That's basically what causes the explosion - the bonds forcing atoms to stay packed tightly into these molecules suddenly break down and the atoms instantly want to fly apart and get away from each other.
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Jan 14, 2014 16:14
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kastein posted:Basically, it comes down to bond energies. Nitrogen gas (N2) has very little energy in the bond between the atoms. Bonding nitrogens together in large numbers (azidoazide azide blah blah blah stuff as many nitrogens as we can into as little space as possible with as few carbons and hydrogens around to keep them sane as we can manage, ohhh cool the fume hood exploded, etc) involves lots of high energy double and triple bonds as well as a lot of funky bond angles that basically put stress on the connection in the first place. So once something (which isn't usually much) bumps the molecule enough to give it the little bit of energy it needs to get started, it simply collapses and all the breaking double/triple/stressed bonds release a fuckton of energy while the N2 gas produced uses very little energy in forming its molecules. Result: a LOT of energy is released and something that was a single molecule in a solid or liquid (say, C2N14) has suddenly become a couple of carbons sitting around while seven N2 molecules head for the hills. That kind of "one molecule turns into seven plus a little leftover stuff when you look at it funny" reaction that requires no real chemical input and very little mechanical trigger is something you want to be very careful around. While mostly correct, you've got one thing fundamentally wrong. The bond energy in N2 is colossal. Thus it's energetically favourable to form N2 as a byproduct of a reaction as it binds up a lot of energy. Ak Gara posted:My next question then is why do 7 N2 molecules take up more room than 1 N14 molecule? I would have thought it would take up the same amount of space. Because N2 is gaseous at room temperature, while N14 is solid. A gas will take up more space than a solid of the same amount of atoms due to the space between the atoms getting larger. It's a principle of explosives. Explosives produce a huge amount of gas very quickly when activated, which is the entire reason behind their explosive property, which forces away rock/projectiles etc. ^^ Beaten twice. 
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Jan 14, 2014 16:16
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And even if they were both gases, the volume of a gas is influenced by the number of molecules present (and temperature/pressure, of course) but not their size or weight.President Ark posted:That's basically what causes the explosion - the bonds forcing atoms to stay packed tightly into these molecules suddenly break down and the atoms instantly want to fly apart and get away from each other. Well, and all the energy that was holding them together is released. The atoms just not wanting to be together is one thing, but in this case, imagine taking a weight to the top of a cliff. You've just given it a huge amount of potential energy. Now let go, and you're turning that into kinetic energy and something is probably going to have a really bad and really shortened day. EDIT: Vitamins posted:Low bond energies are more unstable than high bond energies. Noooooope. Things want to be at the lowest energy possible. Sometimes it's easier to keep them there if it's at some kind of local minimum (imagine a valley between two hills on the ol' bond energy chart), so that you'd have to put more energy in to have it release what's currently in the bond, but lower is always more stable. Ugly In The Morning has a new favorite as of 16:20 on Jan 14, 2014 |
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Jan 14, 2014 16:18
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Also the ideal gas law says the number of molecules matter and not the size. Although for very large or very high pressure gases the ideal gas law is off because the ideal gas takes up no space.
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Jan 14, 2014 16:18
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Ugly In The Morning posted:
I'm an idiot and was talking about bond dissocation energy, not bond energy. I've removed the statement from my post.
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Jan 14, 2014 16:29
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Vitamins posted:I'm an idiot and was talking about bond dissocation energy, not bond energy. I've removed the statement from my post. Haha, now that makes a lot more sense. Stuff with high bond energy is like locking all your relatives in one room- none of them want to be there, they all want to be as far apart as possible, you had to put a lot of effort into forcing them to be there, and all it takes is somebody doing one teensy thing wrong to have it all explode.
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Jan 14, 2014 16:34
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Vitamins posted:While mostly correct, you've got one thing fundamentally wrong. The bond energy in N2 is colossal. Thus it's energetically favourable to form N2 as a byproduct of a reaction as it binds up a lot of energy. Dammit, I knew I'd get something wrong
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Jan 14, 2014 17:28
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N2 gas is basically inert. It's like your overweight college roommate that you needed a forklift to get him out to the bars. But once you do, like sticking a bunch of N on some rings, he goes crazy because he's now some azide death word soup. Then he takes shots of fireball and explodes taking everything out around him. Then he's back to an inert mass on the couch. Oh don't feel too bad about messing up bond disassociation vs bond energy. Thermodynamics is a confusing beast to the untrained.
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Jan 14, 2014 18:36
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DemeaninDemon posted:
I'd be less embarrassed if I wasn't 3 years into a chemistry degree! I always mix that stuff up, I blame being taught in terms of enthalpy. Another fun class of compounds is the ozonides. Made by reacting compounds with C=C bonds with ozone they form a ring with 3 Oxygen atoms single-bonded to each other in a ring with 2 Carbons. Like in the azides mentioned previously, sticking oxygens together is generally something they don't like. These organic molecules are very unstable and like to explode without much stimulation. Unlike the more complicated azide compounds, these are actually pretty useful, allowing carbonyl compounds to be formed relatively cleanly, and in solution these intermediates are pretty safe. The problem comes when you try and isolate the ozonide intermediates. They decompose very rapidly at room temperature and there are quite a few examples where people have tried to isolate them and blown rather large holes in their labs. Most universities don't teach this chemistry anymore, though I do know people who have carried it out. In fact one of my university lecturers knows a guy that ruined a lot of expensive equipment when trying to isolate a primary ozonide.
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Jan 14, 2014 19:22
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This one isn't all that exciting, it's kinda more the other end of the spectrum. Hexavalent chromium. (every materials safety person just shuddered...) It's something like eleven times more carcinogenic than asbestos. And yet it's one of the best anticorrosive coatings/plating solutions in existence, so it's still used in industry, a lot. Oh, that reminds me. Gold colored (zinc chromate plated) bolts? Yeah, don't loving weld those. They're fine in normal use, but if you weld to them, the intense UV and heat from the arc causes the chromate to both evaporate and form new fun chemicals. Apparently (according to a welding safety course slideset I saw a while ago, can't find it now) one of them basically shuts down your liver - it destroys a particular enzyme that you need for your liver to work at all. Silently. And it's a lifetime dose, it doesn't come back, so if you hit the limit, your liver fails. I've welded those bolts before. I have no idea how close I am to the limit. I guess I better be really goddamn careful  (related welding safety note - never, ever, ever loving use a halogenated solvent to clean things before welding. Ever. For any reason. Unless you like inhaling horrible things like chloramine, phosgene, chlorine gas, elemental chlorine, and all sorts of other horrible chemicals that involve chlorine and loving up your lungs/nervous system.)
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Jan 16, 2014 09:51
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Other reason not to weld gold coated bolts is that gold colored plating can also be cadmium plating, which is an equally nasty carcinogen and additionally gives you tons of lung death. Because it hardcore fucks your lungs over regardless of how you contact it (fumes, eating it, etc). I think they stopped using it except for in the military where it's excellent material properties as a coating outweighs the minor risk of poison death.
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Jan 16, 2014 09:57
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