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Sodium + Private Lake = Fun
travisbean writes "This should be enough to pique your interest. Add to the story that the guy has his own pond and I think we can all see where this is going... 'The first step was the procurement, through eBay, of three and half pounds of solid sodium metal for about a hundred dollars. This is a decent price for a small quantity like this. Small being a relative term: It's used by the ton in industry, but anything more than a few grams is a dangerous quantity if found in your home. Three and a half pounds is enough, for example, to blow your home to bits under the right conditions.'"
Bulk metallic sodium runs under a buck per pound (15 cents to a dollar), when you are buying a 300# drum. Prices in smaller lots and higher purity are slightly higher, ranging up to around $35/pound for analytical grade.
The higher purity metal makes little or no difference when you are tossing it into a highly impure natural lake.
I do not deploy Linux. Ever.
My dad worked for the space program on fuel cells for several years. They often had pounds and pounds of lithium to play with in the lake behind the company. They seemed to enjoy making little boats, packing them with as much lithium as they could hold, shiping them out, and throwing rocks at them until it exploded when the boat capsized. They had sodium too, but lithium made a much bigger and louder explosion.
a guy with weather baloons in a lawnchair? nope, I don't think so.
Snopes.com (an Urban Legends site) respectfully disagrees with you.
Up, Up, and Away!
I recall a story from high school (although it may be apochryphal) that a chemistry teacher at my school had been demonstrating the reactivity of various metals and had a number of small chunks of said metals arrayed along his bench in various jars.
:-)
As usual the sodium was kept in mineral oil - and in the story I heard, one of the other (presumably less reactive) metals was kept under water.
When the most trusted kid in the class was left to clean up at the end, they claimed that he'd inadvertantly placed the lump of sodium back into the jar containing water - but that it had not exploded because it was still coated with oil.
The story goes that some hours later, the oil was finally displaced by the water in the jar and the small chunk of sodium then exploded - shattering the entire row of glass jars and spreading exotic and highly reactive metal chunks all over the room resulting in hundreds of small explosions and fires.
I kinda suspect that this may not be a true story though because I can't find a reasonable candidate for the metal that would have to have been kept under water in order for this to be true. However, there was some kind of an explosion/fire in the lab because I remember chemistry classes being cancelled for about three weeks afterwards.
Chemistry classes back in the mid-1960's were much more dangerous than kids are exposed to these days. I clearly recall being given small amounts of metallic mercury to *play* with!! These days, if you so much as crack a mercury thermometer they evacuate the city for three blocks in every direction.
It's a shame, mercury is incredibly good fun to play with - until the vapours poison your brain of course! It's hard to come to terms with something so heavy that's "just" a liquid - and it's amazing how the droplets 'shatter' when you hit them with the end of a ruler.
www.sjbaker.org
I remember reading in an OSS history book about crude time bombs that were made using wine bottles filled with water and gelatin coated tablets of Na metal and/or Potassium. The method was simple: Pop a couple of tabs in the bottle, roll it under a truck or other igniteable item, and you have a half-hour to get away before the water dissolves the tablet casing. The USAAF dropped cases to the French resistance, who used them to little or no effectiveness- not entirely unexpected French-like bevaior.
Sodium is the second lightest of the alkali earth metals. Interestingly, it is the cheapest metal money can buy. Light enough it would float on the water, if it weren't for the aforementioned explosiveness of such contact. Interestingly, the spontaneous reactivity of the alkali metals increases as a function of their weight ... cesium and francium are much more dangerous (or fun, depending on your PoV.)
It's a good thing I read the PTT site a few days ago linked from the IgNoble Awards, because it's slashdotted all to hell now. If it weren't for that, I'd provide you with a link to the Cesium page.
As for Francium, I think I got to read the page for every element he had, and I don't seem to recall him having any. Some of the cool stuff he did have was some Lite Salt (NaCl/KCl mixture) which was measurably radioactive (!) because of a certain amount of natural Potassium is radioactive, and a Fiestaware bowl (which used Uranium as a dye) which was significantly radioactive and for which he made a cast lead bowl in which to store it.
A little bit of trivia: more than a few of the Wolfram Research folks have purchased samples of Tungsten. Why? Tungsten's symbol is W, representing its name in German: Wolfram.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
The teacher who oversaw my senior year independant study in chem had a similar story, though not quite as dangerous. The best part was she had video! Shortly after taking over as head of the chem department she had started to clean out the supply closet of dangerous things that were no longer used (or allowed to be used in many cases) for classes. During this work she found a 2.5lb block of solid sodium in a large oil filled container. Since this was enough to cause a serious explosion she immediately removed it from the school, and after making sure that the container wouldn't leak took it out to the lake behind the adjacent elementary school. She found a .22 rifle and a video camera and made a very educational film, she set the can afloat and rowed about a hundred feet away. There she placed the camera at the bow of the boat and shot the can. About 5 seconds after the can was hit and began to sink there was a massive explosion, so violent that the boat was rocked hard enough to knock the camera back into the bottom of the boat =)
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
He probably does not have a pure sample of Francium, even though it can be found in nature, because it is short lived. Its longest lived isotope is Fr-223, with a half-life of about 22 minutes.
Francium naturally occurs because Uranium-235 has a long half life (7*10^8 years), and it can decay per: U-235 => Th-231 => Pa-231 => Ac-227 => Fr-223 => Ra-223 => etc.
That is the only significant source of Francium in nature.
On the other hand, although the only Plutonium and Technetium on Earth are manmade, he could in principle have samples of these elements, since they have isotopes with reasonably long half lives.
Everything went as planned for a few seconds, then the burning molten sodium caused the same kind of fuel/air explosion as described in the 'Sodium Party' article. The resultant shockwave took the bottom out of the glass(!!) water bath, releasing about 5 gallons of water onto the workbench, along with little bits of fizzing sodium. The gas jar (probably about 1 pound in weight) cleared the adjacent bench, landing maybe 10 feet away.
Having said that, the shock waves and removal of oxygen can kill or traumatise a lot of fish and any birds near the surface. Which makes this a somewhat redneck experiment: I have no problem with people letting off big bangs, but not when they carelessly kill things in the neighborhood.
Panurge has posted for the last time. Thanks for the positive moderations.
Since they didn't have any space to set up lab equipment for us in a regular classroom, we ended up having our "classroom" in the chemical stockroom that adjoined two of the science classrooms. One of my friends got a hold of the anarchist cookbook, and we tried making all kinds of stuff from it, not realizing that a lot of the recipes in there were inaccurate. We made everything from simple gunpowder to nitroglycerine. At one point we had a little mishap where one of the bowls of gunpowder ingnited while both classrooms had students in them. Since we were all honor students, we got a slap on the wrist and continued on as if we never got caught.
Eventually, we progressed to reading old chemistry teaching manuals and looking for experiments that were discontinued. Many were discontinued because the components were carcinogenic, but some were because they were deemed too dangerous. Thermite was one of them, Triiodide was another. If I remember right, NI3 is amazingly simple to make, I think you just mix Potassium Nitrate with crystallized iodine in a water (or was it alcohol?) solution, then filter out the precitpitate. As you mention, it's incredibly sensitive when dry, but if I remember correctly, is a fairly low power explosive. It doesn't put off the huge vapor ratios of your more common bomb ingredients, so aside from the surprise of setting it off, it's mostly harmless in small quantities. It is fun when it pops though, as it gives off a little *crack* sound and a little cloud of purple smoke from the iodine (probably semi-poisonous iodine gas, but unless you're deliberately sniffing it, it dilutes itself quickly enough to not be a real problem).
Anyway, one day after playing around with it a couple times, we made a batch of this stuff after school had let out and while it was still wet smeared it in little patches all over the floor and chairs of the chem classroom that we had for our first period. The next day as people walked in the room, the were random cracks and pops as these tiny puffs of purple kept showing up on all around the classroom. Everyone was quite amused, but aside from the four of us, nobody knew what it was or where it came from. Eventually, at the end of the year right after we graduated we came back and told our chem teacher about all the crap we had done and explained the triiodide on the floors. He gave us a knowing little smirk and surprisingly didn't chastise us at all. 'Course he then proceeded to regale us with all his stories of college chemistry adventures...
All in all, it was a pretty unique confluence of circumstances and provided far more consequence-free fun than I ever would have expected a bio class could.
Since your calculations were pretty much the best (though an AC did correct your final molar results), I'll reply to yours, rather than one of the other 8 people yelling at me. ;p
.13 ppm.) So yeah, even less. I can't think of a single freshwater fish that can't acclimate (easily) to a teaspoon of salt per gallon.
The thing is, you're assuming distilled water. I admit to saying distilled water, but I wasn't really assuming his lake was distilled (for obvious reasons) but I meant that if you combined x sodium with y distilled water, you would end up with a z ppm solution.
A real lake, however, ain't.
I really do believe with the concentration of tannic acid, decaying organic material, and soil interaction of any normal lake, a PH measurement of a lake before throwing in a nice sodium rock and another PH measurement the day after would show a change of 0. It's amazingly hard to change the PH of organic rich water. I don't really have math to back this up, but I do have extensive fishkeeping experience. PH up and PH down are pretty much bunk as products, unless used *very* regularly, as the PH will find its way back to where it started really, really fast. And that's only in 30-100 gallons of water.
And yeesh, as far as excess salinity... I have to dump 7 pounds of salt into 25 gallons of water to recreate the ocean. That's a little bit more than 2 ppm. (though someone with the actual dimensions of his lake worked out
Do you really believe a PH of 8.26 would result? Because... that's just wacky.
One isotope of Francium (223Fr) has a half life of 22 minutes. It's still the most unstable of the first 103 elements though.
Back in college, a ChemE friend of mine called me down to his dorm room to show me the sodium trick. His setup consisted of a ceramic bowl filled with water into which he dropped small pellet-sticks of sodium (removed from a separate oil filled jar). ..err... "experiments" we had conducted before. So I offered my suggestion to pour some magnesium granules into the water and see what happens.. and so he did.
.. which in turn vaporized the water .. ejecting 1000 DEGREE BALLS OF FIRE upward and in every direction. These meteors bounced off the walls, ceiling, and floor leaving holes + scorch marks in everything... the stereo, mattress, monitor, and his roomate's rare collectible $5 bill from 1891.
The reaction was someone impressive but not nearly as some of the other explosives
To our surprise, what followed involved more physics than chemistry...
He dropped in the sodium, which fizzed around for a few seconds, burst into bright flames.. igniting the magnesium granules
Luckily my body was protected by the door and my face with a plastic report cover.. heh heh heh.
Kids don't try this at home.