Slashdot Mirror
The Delights of Chemistry
Dan Ormsby writes: "No news on this site, just great photos of chemical phenomena along with instructions on how to perform them yourself. Don't try this at home!"
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Check this:
LNUX + IPO = $0
why the fuck not?
Why do we get instructions on how to do it?
http://crummysocks.com
bitches
Christ, what kind of childhood would I have had with THAT kind of advice?
Why is Slashdot so slow all of the sudden? What is with this "Nothing for you to see here, move along" crap?
insert your own lewd reference here.
Your mind is squeezed by a blast of pain!
This will be /.'ed before you can say H20
Better living through cocaine. Artificially induced libertarianism, as it were.
http://www.google.com/search?= cache:U69NL26L50Y:www.chem.leeds. ac.uk/delights/+&spell=1
hl=en&safe=off&q
Just how many of these experiments are copyrighted? i don't wanna pay the powers that be for the privilege of a cheap and easy chemical burn.
and I already checked for a google cache. Too bad Hemos didn't give us his own witty commentary, so at least we could make fun of that while waiting for the site to go back online.
xxx straight edge xxx
I remember finding a book of chemistry experiments, and being fascinated with what I could do with just mixing a couple things.
:)
Not simple stuff like "wow, vinegar and baking soda" (although kitchen chemistry is very cool), but "wow, battery acid, zinc and limestone will make lethal chlorine gas! cool!". (iirc)
While I don't want MOST kids getting that spin on it (:D), some golly-gee-whiz experiments at a YOUNG age, with some more every year, will help keep them interested in learning. And up here in Canada, at least, we've got a big problem with keeping boys interested in learning. But boys like things that go bang. Simple solution.
NEW YORK (Reuters) - For some, a new stock offering gone awry is worth more than a successful one.
Lawyers are the only characters involved in the initial public offering drama of the late 1990s still making money as a consequence of those deals, and keeping their reputations clean so far. The other actors -- disgruntled investors, ailing dot-coms and investment bankers under regulatory scrutiny -- are licking their wounds.
A rash of lawsuits by investors trying to recoup losses in IPOs is turning into a boon for the legal profession. The suits are bringing in steady fees at a time securities-related business, like IPOs and merger advisory, is tapering off.
Lawyers aren't earning the kind of money made by the Wall Street banks that helped companies sell their shares, typically 7 percent of the raised capital. Nor do the fees amount to the estimated $3 million in stock and cash law firms made on a typical hot IPO last year.
But it's still a steady flow of cash -- at least several hundred dollars an hour -- that increases each time a new IPO-related lawsuit is filed. And that happens every day.
``Representing companies in securities litigations is very respectable and remunerative,'' said Scott Schreiber, attorney at the Washington, D.C.-based law firm Arnold & Porter. Law firms are paid mostly by the hour, but in longer cases they can receive a monthly fee, he added.
To be sure, law firms that specialized in high-tech start-up companies are feeling the pinch of the dot-com bust. Cooley Godward of San Francisco recently laid off 13 percent of its attorneys partly because its once blossoming merger advisory business had dried up.
But defending against angry shareholders is booming.
More than 150 companies this year have been sued in over 700 complaints alleging that secret agreements between the companies and their underwriters artificially inflated stock prices on their first trading day. The shareholders have not yet sued the IPO's legal advisers, and two experts told Reuters lawyers can't be held liable for their work on a new stock offering.
The list includes most of the companies whose stocks enjoyed the biggest first-day gains ever, up to 600 percent. Names like software makers FreeMarkets Inc. and VA Linux Systems Inc., and Internet data delivery services provider Akamai Technologies Inc.
Most of the corporate defendants have gone back to the law firms that signed off on their IPO prospectuses. The first hearing for the cases is scheduled for next week in the U.S. District Court for the Southern District of New York.
Legal fees are among the highest fixed expenses for a company wanting to go public. In 1999 they amounted to about half a million dollars. In many cases -- over one-third of the 450 IPOs closed in 1999 -- lawyers also bargained for shares in the public company-to-be.
Those stock awards amounted to an average $1 million (at the time of the IPO) in 1999 and $2.3 million in 2000, according to research firm Equilar Inc.
Stock compensation has lost its allure in the slumping stock market. This year, only nine law firms have accepted shares in lieu of cash to advise an IPO. The average legal fee, in the meantime, has jumped to $1.1 million.
The amount law firms can pocket during a civil suit depends on the length and complexity of the case, and some say the sum can top an IPO's legal fees.
``There is big money to be made in those cases,'' said Jennifer Vaughan, executive editor of the Class Action Law Monitor, a twice-monthly magazine of Strafford Publication Inc.
Some of the nation's biggest law firms, which had a role in the hottest IPOs, told Reuters they now are representing these same companies against the shareholder lawsuits.
Cooley Godward, which was legal counsel in 90 IPOs over the past three years, represents nine sued companies, including Tivo Inc.
Testa, Hurwitz & Thibeault LLP is working on the litigation of Red Hat Inc., among others. Wilson Sonsini Goodrich & Rosati, the largest law firm on the West Coast, which participated in 210 IPOs since mid-1998, represents VA Linux, whose shareholders are trying to recoup huge losses.
``When it comes to IPOs, lawyers have the best part of the deal,'' said John Fitzgibbon, editor of IPO Desktop. ``No matter how they turn out, for them it's a win situation.''
but I couldnt help notice they didnt include pictures of a Glass Bottom Boat
Their current stock valuation is less than their cash reserve as of last quarter's end.
Demonstrations 04 & 05
Flammable vapours
Continuing the theme of combustion this is an attempt to model an incident that occurred in a small garage local to where MH lives in Sheffield. In these spectacular experiments dihydrogen, diethyl ether and alcohol are burned.
Liquids that vaporise easily at ambient temperature to form heavy vapours pose particular hazards during handling e.g. when transferring from one container to another, or when spilled.
Petrol is the most common of these fluids and serious accidents have occurred during handling due to flashback from sources of ignition often at considerable distance away. Because the heavy vapour spreads along the ground it does not readily defuse into the air and become diluted below its explosive/flammable limit so the, even outdoors, it can be very dangerous. People attempting to kindle garden fires or BBQ's with petrol have all too often been engulfed in flames due to the spread of the vapour beyond the intended area. Similarly liquid petroleum gas (LPG) has also caused appalling accidents when 'fire balls' have formed due to the ignition of dense clouds of the gas. Butane has a density of more than twice that of air.
These experiments attempt to simulate, and so demonstrate, this phenomenon. Diethyl ether is used because it has a combination of high vapour pressure (440mm Hg at 20C) and density (2.55 {air = 1}) and has been responsible for many accidents in the laboratory and the chemical industry where it is often used as a solvent in chemical processes.
In the first demonstration a length of extruded aluminium angle is set up to form a channel along the length of the lecture bench (some five meters) such that one end is at bench level and the other some 150cm higher. In the video this is said to represent the floor of a garage (set sloping in order to reduce the experimentation time) and a wad of burning cotton wool soaked with a little alcohol at the lower end is said to represent someone welding (a source of ignition). Balloons are attached at the high end. These are filled with hydrogen gas except the yellow one to which a little oxygen had been added in addition to the hydrogen (the story line has these to emphasise the effect of a leaking fuel tank exploding). Sufficient diethyl ether wars added to the high end of the channel (representing a petrol leak) such that it was all vaporised by the time it had reached about half way down. The heavy vapour continued down the remaining 2.5m and was ignited on reaching the 'welder'. The thunderous sound of the explosion it impossible to reproduce from the video but some compensation is afforded if the exploding balloons are played back frame by frame.
The speed of the (defusion) flame front along the channel was quite slow due to the lack of mixing of the vapour with the air. In reality air movement, particularly if it were outdoors, would pre mix some of the ether and air. The second experiment attempts to simulate this. The storyline here is that the space enclosed by the Perspex safety screens represents a laboratory and the candle represents a Bunsen burner. Diethyl ether (15ml) is spilled on the floor a metal tray and left to evaporate. Later a small electric fan is started to create a draught and so mix the vapour and the air. When this pre-mixture reaches the source of ignition the resulting conflagration is very rapid and if were much larger or confined, an explosion would occur. See also experiments 7 and 15a.
This is one occasion when seeing it in real time is less impressive than the series of single frames, there are 25 each second. The series of diagonal stripes from top left to bottom right, to be seen on one of the frames, are vertical, or near vertical, oscillations (pressure regions). They are slanting because of the way the image is scanned by the camera, left to right, top to bottom.
By using video frames as units of time (each represents 40ms) the relative velocities of the near diffusion flame-front and the pre-mixed flame-front can be, roughly, determined. Since the same synchronisation pulse as received by all three cameras any combination could be used for this purpose. I used camera three for the (near diffusion) flame on the channel and counted the number of frames that showed it passing the front of the safety screen enclosure. The images on the video are from another camera and are not useful for this. I used frames from camera one for the pre-mixed flame-front which is the one use for the video at that time. I got the following results:
Number of frames taken for the 'diffusion' flame to traverse the enclosure front = 17 (= 680ms)
Number of frames taken for the pre-mixed flame to traverse the enclosure front = 7 (= 280ms)
Relative velocities 680/280 = 2.4.
So the pre-mixed flame travelled about two and a half time faster than the diffusion flame. However, until the flame was bounded by the walls of the enclosure the increase in volume was 2.43 faster i.e. about 14 times!
HAZARDS
The main hazards are exemplified by the demonstration itself. . Diethyl ether has a high vapour pressure (440mm Hg at 20C) and density (2.55 {air = 1}) and a low auto ignition temperature (not flash point!) of between 180 and 190C. Air/ether mixtures containing >1.85% v/v of diethyl ether vapour are constitute an explosive hazard.
Explosive peroxides (ethylidene peroxide polymers') may be formed on exposure to air and light, and particularly when evaporated to dryness. These peroxides have been known to form around the stoppers of container of diethyl ether that have been left unopened for long periods. Although not relevant to this experiment it is worth pointing out that ether is a good electrical insulator and when very dry (saturated ether contains 1.2% water at 20C), shaking etc. can produce sufficient static electricity to cause ignition of the vapour.
Diethyl ether is mildly irritating to skin and mucous membranes. Inhalation of high concentrations causes narcosis1.
Hydrogen gas is very flammable and yields explosive mixtures with air. The stoichiometric mixture should be avoided because the explosion is too loud. The audience should be, at least, three meters from the balloons.
DISPOSAL
Immediately after the explosion a careful check should be made to make sure that no debris from the balloons are burning2. I have performed this demonstration over 70 times (>280 balloons) and have not found this to happen but one should be aware that it could! The cotton wool should be extinguished by covering with a watch glass and left to cool.
References.
1. P. G. Stecher, (Editor) The Merk Index Eighth edition, 1968 p. 483
2. B. Iddon, The Magic of Chemistry BDH Product Code: 57045 ISNN: 0 9800439 6 6 1985 p. ii
Excuse me if I'm wrong... but doesn't the title here in my browser say "Slashdot: News for Nerds. Stuff that matters.
How did this make a headline?
As far as explosives go, lots of cool things to do with chemicals like magnesium and nitrates. Just might have to search a bit harder. `8r) But hell, just making hydrogen is fun, from electricity and water.
Gonzo Granzeau
"Nothing the god of biomechanics wouldn't let you into heaven for.." -Roy Batty
finally proof of what goes on inside when you eat Cornflakes
I always wanted to do this but was never allowed although I tried it with flower but got much worse results
if you really like to blow things up custard powder rocks !
this is why in medieval times they never allowed candles in the mill
regards
john jones
... there are not captions, or explanation (theoretical or "proven") of how the chemical mechanism works! Unless it's so simple that it should be self-evident...
[BOOM]
"We're going to need a new Timmy!"
[Guess the source?]
I mean, I'm all for Chemistry and all that, since the physical sciences pay for my grant, but this is just a random university website: why is this front page worthy? Was there no Microsoft news today? Or is this symptomatic of a general decline in the tech sector?
"I will take the Ring," he said, "though I do not know the way."
Not to plug my own site, but we have a really cool "fire in the bottle" how-to video.
Wooden armaments to battle your imaginary foes!
I WANT TO BUTTFUCK A MAN
i want to buttfuck a man
Let's post really obscure articles with absolutely no details, that way we can be sure the /. effect kicks in asap...
Think outside the... Hey, where'd the friggin' box go?
Science: The Delights of Chemistry
Posted by Hemos on Thursday August 30, @03:15PM
from the ka-RASH dept.
Dan Ormsby writes: "No news on this site, just great photos of chemical phenomena along with instructions on how to bring a website to a grinding halt. Don't try this at home!"
If you liked that, you might also want to check out the physics demonstration archive at my old school (UMD).
IIRC It's the largest in the country.
Oh yeah, the Question of the Week is also very good.
Now that I took a second job where I have access to a professional Chemical lab. Something to do when I get bored with what I an supposed to be doing.
I also remember another demonstration in which he blew the lid of a can. I can't remember what he did then though.
Great teacher, if it weren't for his preparation I wouldn't have been able to get a 5 on the AP Chemistry test.
My only political goal is to see to it that no political party achieves its goals.
comp-u-geek.net link in that cache!
Enough with the scientology crap, dingdong. Don't post copyright materials here.
Can someone kindly explain how the moderating system works. Didn't quite know where else to ask this question. Sorry if I broke up the thread here.
.
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29jan0
Wait until they put up pictures of their web server exploding from the /. effect...
sig fault
Rhodium
Phenethylamines I Have Known and Loved
Tryptamines I Have Known and Loved
Erowid
Lycaeum
I'm posting this again because slashdot keeps rejecting it.
http://www.msnbc.com/news/621827.asp [msnbc.com]
please don't click this line, I'm avoiding the lameness filter
Aug. 30 -- It's easy to load a small library of electronic books into your laptop or handheld organizer and carry it with you on the bus or to the beach. But try to make backup copies of those same e-books or loan one to a friend, and you'll run smack into the digital equivalent of an electrified fence. The problem is that once a literary work has been liberated from the printed page, it's potentially vulnerable to unlimited digital piracy--a danger that makes most e-book publishers insist on strict software controls to prevent anyone but the purchaser from opening an e-book file.
COMPETING "digital rights management" systems offered by companies such as Adobe Systems, Microsoft, Reciprocal and ContentGuard allow publishers to outfit e-books and other forms of electronic content with customized usage rules. The companies naturally strive to make these systems as hacker-proof as possible. But Technology Review recently learned of a home-brewed decryption program that defeats the most advanced antipiracy features built into Microsoft Reader, a leading e-book program downloaded by over a million people since its debut in August 2000.
(MSNBC is a Microsoft-NBC joint venture.)
CODE BREAKING
The decryption program enables purchasers of "owner-exclusive" Microsoft Reader titles--Microsoft's most highly protected form of e-book--to convert these titles to unencrypted files viewable on any Web browser. The program's creator, a U.S. cryptography expert who asked not to be identified, says he wanted to circumvent the "two-persona" limit, a rule built into Microsoft Reader at the behest of publishers that allows purchasers to read the same e-book on up to two devices, but no more.
Though the decryption program works on any Windows PC, the programmer hasn't released it, saying he developed it for his personal use. But the program's existence, together with decryption efforts directed against e-book formats from other companies, such as Adobe, illustrates the vulnerabilities in digital rights management schemes. It also promises to fuel the ongoing debate over the 1998 Digital Millennium Copyright Act, under which it is legal in certain circumstances to use--but, paradoxically, not to make or distribute--software that circumvents technological copyright protections.
Microsoft controls access to copyright-protected e-books through Microsoft Reader, the software used to display e-book files. Reader is a free program that can be installed on any Windows laptop or desktop. When you purchase a Reader e-book from a retailer such as Amazon.com, special server software equips your title with one of three levels of copy protection, as specified by the publisher.
E-books with owner-exclusive protection, the level used for premium titles such as current bestsellers, are encrypted during download using a unique mathematical key contained in your copy of the Reader software. This key is obtained by "activating" your copy of Reader, which requires you to register for a Microsoft Passport account and supply Microsoft with an e-mail address and other identifying information.
Currently, only two copies of Reader can be activated under the same Passport account--the "two-persona" rule--so access to owner-exclusive e-books is limited to the devices on which those two copies of the software are installed.
READERS RESPOND
Such rules irritate many e-book readers, who feel that once they have purchased a book, they should be able to read it wherever they want. "I like to read e-books at my desk, when I'm traveling, lying on the sofa and when I'm eating lunch. I use different computers for these things, so I need more than two activations," says Roger Sperberg, a publishing consultant and a columnist for the industry site eBookWeb.
Some readers also complain that Microsoft's limitation makes it difficult to recover their e-books after a hardware upgrade, which can invalidate the activation key. The anonymous programmer says he wrote his decryption software partly to sidestep such practical problems, and partly so that he could extract the text of his e-books for display on additional devices such as the REB1100, a dedicated reading device manufactured by RCA.
The programmer's software works by recovering a series of well-hidden encryption keys specific to each activated copy of Reader and to each owner-exclusive e-book. It essentially reverses the process that publishers follow when they assemble source files such as text and images into a final e-book. The software dumps unprotected copies of these files into a new folder on the user's computer--as the programmer demonstrated to Technology Review using an actual owner-exclusive e-book purchased from a major online bookstore.
Approached for comment, Jeff Ramos, director of worldwide marketing for Microsoft's "eMerging Technologies" group, said, "We do not comment on alleged security violations of our software. In general, if necessary in response to such incidents, we take appropriate measures."
DIGITAL-RIGHTS DEBATE
So far, programmers intent on exposing e-book security weaknesses haven't been deterred, even by the possibility of legal action. Indeed, the publicity surrounding the prosecution of Dmitry Sklyarov, a Russian cryptographer who wrote similar software that strips copy protection from Adobe e-book files, has only added to widespread criticism of digital rights management technologies and the laws designed to bolster them.
FBI agents arrested Sklyarov at a July hacker convention in Las Vegas after a tip-off from Adobe that Sklyarov's employer, ElcomSoft, had been selling the protection-removing software from its Web site. The arrest--the first criminal case brought under the Digital Millennium Copyright Act--spurred a boycott against Adobe products and protests against the company in more than 20 cities around the world. (Adobe quickly withdrew its support for the prosecution, and Sklyarov was released from custody in August. The U.S. Department of Justice continues to pursue the case.)
One issue in the Adobe debate is a conflict in the copyright act. An exemption to the legislation makes it legal to circumvent technological protections when an e-book is malfunctioning, damaged or obsolete. Civil-liberties groups such as the Electronic Frontier Foundation say such exemptions are necessary to protect traditional rights of "fair use" of copyrighted materials. But the act outlaws the manufacture, distribution or sale of software or devices that would allow consumers to exploit the exemption--a provision supported by publishers.
"There is no device that can currently distinguish between a fair use and an illegal use of a copyrighted work," explains Allan Adler, vice president for legal and government affairs at the Association of American Publishers.
But unless publishers give readers the leeway to use e-books the same way they use print books, say many critics, few consumers will ultimately buy into the technology. To eBookWeb's Sperberg, getting rid of the "crazy catch-22" in the copyright law and rules like Microsoft's two-persona limit would be a good start. The fact that Microsoft has now joined Adobe as a victim of e-book decryption efforts, he says, should make it clear that "digital rights management doesn't make things harder for the professional pirate or the black-market publisher; it makes things harder for me, the reader."
Until software makers and publishers can figure out how to protect their e-books without treating all readers like thieves, in other words, the summer of beach-blanket e-books may never materialize.
ascii spork
Cripes, I feel for these sites that are unknowingly featured on
even though it says dont try this at home, i did.. and well, i burnt my penis off and my balls shrunk to something resembling raisins. who do i sue?
...
It's a goatsex link, unfortunately. Wish there was a real mirror.
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I present The Terrorist's Handbook
...on of the more interesting ones out there. Oh, if that link doesn't work try here instead.
It's illegal to posess chemicals or use normal products inconsistant with their labeling. A local guy here who was into electronics and chemistry was brought up on charges under some "anti-terrorism law" and for having "drug paraphernalia" (aka graduated cylinders, a pipet, soldering iron, etc) and was sent to prison for 24 years and 7 months. Watch out folks it's not just explosions or burns that'll get you, the law is out there too!
and he also had all his equipment confiscated.
The Giant Artificial Poo! Although if you have sulfuric acid in your digestive tract, you're more of a man then I am.
And the brethren went away edified.
Random User writes: "No news on this site, just great photos of home-made explosions along with instructions on how to make home-made pipe bombs by yourself at home. Don't try this at home!"
Uh, here it is, complete with instructions..
You are truly stupid. Do you have no idea what's going on? Do you not realize that the site is /.'ed? This is the complete opposite of "offtopic", it's, by definition, on topic, as it is a MIRROR FUCKING COPY of what nobody else can see.
I was interested to see the "Barking Dog" reaction, because my high school chemistry teacher performed a chemical demonstration which produced a dog-bark sound. The reaction was different, though, and I'm wondering if anyone here has seen anything like this.
What my teacher did was to dissolve white phosphorus in carbon bisulfide, soak a circle of filter paper in the solution, and lay the paper over the mouth of a large (maybe 1 liter) graduated cylinder. The carbon disulfide quickly evaporates, leaving a residue of phosphorus on the filter paper, which spontaneously ignites, sucking the air out of the graduated cylinder...and making a sound like the barking of a dog.
hyacinthus.
Although I don't pretend to know much beyond OSHA HAZWOPER taught me about chemical regulations, perhaps the reason for some of the more exotic/dangerous solutions might be that these people are based in Leeds, which is in the UK. From what I have been told by my British chemistry teacher Mom, regulations are a little more lax in the UK.
...and I've come up with a revolutionary new compound. I call it "nigger and jew pesticide." I will begin commercial production in handy aerosol cans for easy and fast application for those tight situations. It's a pretty simple... it consists of carbon and nitrogen. I'm suprised no one discovered this yet. It works amazingly well! Hell, it works so well I've been thinking of using it in those "community bathouses" all those fags buttfuck eachother in. Maybe I can add fag to the list of uses.
I don't think I'd want anything like that passing through my digestive tract. I always heard that feces were undigested fiber and dead bacteria. The "turd" in that experiment is just a piece of incinerated sugar. By the way, where is the professor's protective goggles and lab coat, and what about ventilation equipment? You can see the fumes rising from that black gunk.
Roanna
Please visit ZOID CITY Community and Community Competition http://www.zc2zc3.st
OK, I skipped all the demos. I enjoyed chemistry but hated the labs. On the bottom of the page is a link to one of the web's most gorgeous periodic tables. Each group of elements is a different rainbow color.
If you click on each element you see an image of it in nature and get its history. If you click on the chemical information you see its image in pure form.
There are quicktime movies and Shockwave demos too. This is not the visual periodic table for nthing.
Roanna
Please visit ZOID CITY Community and Community Competition http://www.zc2zc3.st
Reading over the experiments listed on the site reminded me of one experiment we did in honors high school chemistry which was NOT included. Our "teacher" was actually someone from the art department who was pressed into service as a chemistry instructor because he had a few chemistry classes in college. He walked in one day with a freaky, glazed look in his eye and announced to the class that we were going to be doing an experiment to start the day. He went into the back room, came back with a pair of tongs and bottle of kerosene containing a chunk of potassium metal, and gestured for us to join him outside. We gathered around a large rain puddle from the previous day's storm, and he asked what class was in the room next door -- English, as it turned out. Without any additional explanation, he reached into the bottle, grabbed the chunk of potassium with the tongs, flung it into the puddle, and stepped back. After a few seconds, the metal predictably exploded with a VERY loud bang, causing 35 English students to scream in unison and then rush to the window. The chemistry teacher stood there with a goofy grin on his face, and then shook his head and muttered to himself, "Yup...it's exothermic all right." (For those who read the article, he also did the thermite experiment during the year, but put about three times the recommended amount of magnesium in each student's setup. There were metal chunks in the ceiling tile for years afterwards...)
"she says i'm lousy conversation. as if that's supposed to help."
An interesting thing to note about chemistry demonstrations: Having participated in several demos at elementary schools, I've noticed that it doesn't matter what you blow up or set on fire, kids are always more impressed by do-it-yourself Gack/silly putty. Go figure.
... Everytime he made an experiment it exploded.
;-)
My favorite "kitchen experiment" is igniting a mix of flour and air to show that any powder being relatively explosive (very fun not to try at home)
But the most violent explosion was mixing H2 and Cl2 and igniting with a laser beam (really NOT try at home, explodes at light exposure
Back in high school one of the home economics classes had people carry around flour or sugar "babies" (I think both were used). During that whole time I wanted nothing more than to find a forgotten sugar baby and dump sulfuric acid on it before returning it to the home econ department. I believe they would have considered the baby dead and failed whoever lost it.
Everytime you look at porn a devil gets their horns.
Add some iodine crystals to liquid ammonia (you just need the stuff that's dissolved in water). Filter and don't dry!
I remember the time I made my biggest batch ever. About two tablespoons worth. It was family reunion and I put the stuff in blotting paper on my windowsill to remove excess liquid.
I called my cousin, told him I've got something cool to show him. Took the paper, semi-dry now, walked through the crowded living room, went out the door. Shut the door, said, "This i..." and things got fuzzy here.
Right, next thing I remember my hand was blue-purple, without feeling and I had this zinging noise in my head. He was staring at my hand like he's never going to see it again...
So, the lessons here are:
Well, have fun!
"-and those damned stupid barbarians with their damned stupid swords will win after all..." -- Larry Niven (The Magic Goes Away)
I seem to remember a friend doing this in Chem II class in high school, and getting detention for a week in the process.
Mr. Parker, I wonder if you (or your kids) read Slashdot...
Oh, what glorious fun we had with thermite, with a VERY small bit of sodium in chlorine (yikes!), with deflagrated oxygen and red phosphorus.
We never did get around to the filter-paper-soaked-with-perchlorate "land mines" that pop under your sneakers, but we *did* talk about it.
"How many light bulbs does it take to change a person?" --BMcC-->
Was when I was a senior in high school, the chem teacher caught some students heating a test tube filled with finely powdered zinc and sulfur mixed together out in the open. He took their test tube away from them and griped them out, then he wanted to show the entire class what would happen, so he put the test tube in a clamped stand over a bunsen burner inside the fume hood and closed the big thick oak and bulletproof glass door of the fume hood. The mixture heated for several minutes and everyone's attention span gradually faded away, then when everyone least expected it, the thing exploded with enough force to knock the thick oak door off the front of the fume hood and the glass popped out of the frame and hit the floor and broke. There was nothing left of the test tube and the clamp stand and bunsen burner ended up as shrapnel. Frightened the crap out of everybody in the room. The school principal came running down the hall to see what happened and everybody in all the other classrooms nearby came running also to see if anybody was hurt. The chem teacher got into big trouble.
The demonstration you talk about is how I learned
:)
about lab safety in high school (the hard way).
For my final demo in high school, I had bored a hole in a slab of dry ice (which is
rather difficult to do) and placed some magnesium powder in it. My chemistry teacher also recommended that I mix in some potassium chlorate (strong oxidizer) in there.
Well, I prepared the mixture, got another slab of dry ice to place over it, _held it down with my hand _(with the chemistry teacher watching), and lit the fuse.
I should have noticed the evil smirk on the teachers face as I did this...
What resulted was a little explosion right under my hand that broke the glassware on the bench and scared the daylights out of me. Luckily, the debris had spread out laterally, and I was not hurt.
Other things I learned not to do by watching others in high school:
-Do not stick your hand in forming polyurethane
-Do NOT set up an experiment that produces gaseous copper
-Phosphorus left in the sink will catch fire spontaneously in the middle of class
-elemental sodium is not a toy
Moral: always trust your own [hopefully paranoid] judgement about lab & on the job safety.
Next time: how to alarm bedroom community with "improvised thermite"
BTW, our textbook was Chemical Demonstrations by Bassam Z. Shakhashiri.
Some video of: Fun with Liquid Nitrogen and Fun with High Voltage Electrical Discharges
Long ago I dated a chemistry grad student and he told me: "There are old chemists. There are organic chemists. There are no old organic chemists."
Roanna
Please visit ZOID CITY Community and Community Competition http://www.zc2zc3.st