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12AX7
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Acetylene doesn't smell like garlic, it's odorless... it's the trace elements with the carbide that causes that, remember?
Tim
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The_Davster
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It is phosphide impurities in the CaC2 reacting with water to produce phosphine which is the garlicky smell you refer to.
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Fleaker
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Acetylene doesn't smell like garlic, it's odorless... it's the trace elements with the carbide that causes that, remember?
Actually acetylene/ethyne has quite a pleasing smell when pure Tim.
Impurities give it that odor.
[Edited on 8-9-2005 by Fleaker]
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kclo4
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well i just did my first "life" threatening "trick".
I had just got done distilling some HNO3 from H2SO4 and NH4NO3. i heard a small part of the distilling flask crack, now i was a little bit hurt from
my new still having a small crack in it but i was afraid that it would brake and have all the hot HNO3/H2SO4/NH4HSO4 go all over my stove making NOx
and stuff. so i got a bunch of "emergency" water Na2CO3 and NaHCO3 ready for the cato but it never happen. But as i was putting on the lid
to my reagant bottle i twisted it just a little tiny bit and the bottle holding at least 150 to 200 mls of red fuming nitric acid broke in half, and
making a sharp shard of glass go into my hand cutting a nerve as while the HNO3 got on my pants and all over the floor(only a little bit got on my
pants say maybe a 5mls). I ran to my sink and sprayed water all over me then i put some carbonates on the spill and took a shower my hand finally
stopped bleeding and i was thanking god that i was warring my face shield!!
Grrr what a waist of HNO3 and blood.
oh ya i was wearing a T-shirt and have over 40 nitric acid droplet burns on my arms!!!
what will happen if i get a little bit of HNO3 in my blood (we are talking almost nothing at all)
has anyone had reagant bottles break really easy?
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kbk666
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Most ignorant thing I probably did was when I was synthing TNP and wore latex gloves...It eats through latex ya know (I sure didn't).
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Magpie
lab constructor
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klco4 says:
Quote: |
But as i was putting on the lid to my reagant bottle i twisted it just a little tiny bit and the bottle holding at least 150 to 200 mls of red fuming
nitric acid broke in half,
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Was this a regular reagent bottle designed for nitric acid? Do you have any explanation for why the bottle broke?
The single most important condition for a successful synthesis is good mixing - Nicodem
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kclo4
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Well, IDK what a nitric acid bottle is.......
It was one of those narrow necked reagent bottles from pelletlab (i figured it would work great nitric acid since it is stained glass)
Some of the other ones I have, have are bubbles in them that are stretched out. But I would not think this be the reason, it must be because the
bottles there are crappy or something IDK.
Fun Fact: if i bend my hang just the right way i can see muscle or something way passed the skin.
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nocturnal shadow
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back when i first discovered Ap and was young and stupid i was trying to impress some friends. so first i put a little bit of AP (about the size of a
pea) on the ground and hit it with a hammer, pop. so trying to be cool i put a bit of a pile down (a couple of teaspoons) and hit that, it made the a
huge ka-boom and me and two of my friends shat ourselves and my ears where still ringing half an hour latter, but the funniest thing was his next door
neighbour who was hanging out washing 20 metres away, the look on her face after the boom when all she could see was me lying on my back with a hammer
made all the hearing damage worth it.
Nights my ally, Darkness my friend
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Douchermann
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Haha, one of the most ignorant things i've done, was a long long time ago I used to rip apart fireworks and play with the flashpowder, well once
I ripped appart a ton of fireworks and filled a little toy car with the flashpowder. Luckily nothing happened (the fuse didn't work right).
Another thing was I was generating ammonia gas, and I mixed the NH4NO3 and NaOH together, and it turns out the NaOH had water on it, and the reaction
started. I didn't know this at the time so I took a big breath and got tons of ammonia gas. TextGreen
It\'s better to be pissed off than to be pissed on.
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DDTea
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My whole Chloropicrin experiment was stupid. But the stupidest part was when I was unsure if it was successful, so I took my gas mask off and sniffed
the reaction beaker.
It was successful.
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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The_Davster
A pnictogen
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Today at uni, I was drying glass with a bunsen burner in preparation for a grignard reagent synthesis. A just dried graduated cylinder rolled off my
bench....I caught it I got blisters on my fingers immediatly. Damn these
hurt...
How was I so stupid....
[Edited on 17-3-2006 by rogue chemist]
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rot
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A few years ago I was experimenting with dynamite, and decided it would be fun to put some into a large chunk of concrete, I had a very small fuse
(from a firecracker ). It detonated when I was only 10 feet away and pieces of
concrete went everywhere, the matchbox that I dropped onto the ground after lighting the fuse was ripped to pieces by the flying rocks, if that was my
head I could have been dead.
Some time ago I wanted to make calcium chloride for drying my nitroglycerin faster, from chalk (CaCO3) and HCl. I didn't know that this would foam
alot, the acid was spilled all over the floor leaving me with a nice mess to clean up.
Recently I was purifying ammonium nitrate from fertilizer, something I did a 100 times. I was making a lot, so when it was boiling down I got
impatient and went away to watch some TV. 10 minutes later my neighbour came to my home complaining his garage was filled with smoke. (we share the
same garage, seperated by a wall but at the top there is a gap) The AN decomposed because I heated it for too long.
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woelen
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In my younger years, my favorite experiment was electrolysis of a tablesalt solution. I used 9V batteries for that, but the speed of the reaction was
soooooo low...... I needed something more powerful.
One evening, I decided to take two electrical wires and made a plug on one side of both wires and the other side was left open with two pieces of
copper wire sticking out of the isolated wires. I immersed these wires in a tub with 0.5 liter of water, with some table salt dissolved in it and then
put the plug in the 220V wall outlet. A nice vigorous reaction started, gas was produced. I was watching this reaction, it looked nice. I was watching
it from above. A green flocculent precipitate was formed slowly as well (I now know from the copper wires, both slowly dissolving, due to use of
AC-power).
I did not notice, that the wires slowly moved towards each other. I just was watching the fascinating reaction .... suddenly there was a very bright
blue flash, a loud crack and glass shattered all over the place. The salt-water content was splashed into my face (it was luke-warm). Then it was
dark.... the fuse was burnt.
What happened, is that an electrical short circuit was formed and a tremendous amount of power was released, causing a small explosion under water.
The liquid was blown into my face, but the explosion was so powerful, that the glass jar was shattered. Luckily, I had no painful things. The liquid
was only luke warm and it was a dilute salt solution with just a small amount of the green precipitate, it was not particularly toxic or corrosive.
The glass jar was broken, but the force of the glass flying around was not large. The only things I had to do was replacing the fuse and cleaning up
the mess before my parents arrived (they could arrive every moment).
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jack-sparrow
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Here is my DO NOT DO list :
1) Pt/C in methanol (ignites violently)
2) Vacuuming an acetylene bag with an electric lab water-aspirator (explodes)
3) Synthesize a gas in a 5 steps synthesis and forget to keep filling the cold finger condenser with acetone/dry ice at the distillation step. Lost
10000$ worth of product
4)Forgot to secure stopcocks while distilling a highly valuable solvent. Solvent bumped, stopcock went away, lost 25000$ of products.
5)Manipulate a COLD 5L round-bottom flask filled with 500g of benzaldehyde and 4.5 L ether with nitrile gloves. Condensation AND nitrile gloves is a
leading cause of RBF drop on the floor and a nice afternoon of cleaning a smelly mess.
6) More to come ... But not too much I hope![:D](./images/smilies/biggrin.gif)
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DrP
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Not me I hasten to add, but my GF was teaching in the undergrad lab last week and was asked by one girl why she wasn't getting a vacuum on her buchner
flask....
... she had connected the rubber tube which pulls the vacuum to the clamp rather than the buchner flask which the clamp was holding! Outstanding
lack of understanding!!!
Once however, I managed to get the tube twisted in the sink when leaving some polymer to filter. Instead of going down the plug hole, the water
sprayed up behind the sink unit. I dind't notice this and left the thing sucking all day.... ....which flooded the labs on the floor below much to
the displeasure of the caretaker!
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jack-sparrow
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Here are some other examples (not mines) taken for undergrad labs.
1) Putting glass wool in a separation funnel !?
2) inflating a rubber pipet bulb with compressed air until explosion (impressive AND plain stupid) It can easily contains 50L of air
3) Rinse an erlermeyer flask with water, then filling the erlen with acetone (completely) to remove water traces...
4) Washing an organic phase with sodium bicarbonate, discard the organic phase, evaporate the aqueous phase and get a wonderful and generous amount
of white solid which you THINK is your product !
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Magpie
lab constructor
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Sturdur, those are downright funny. I never saw anything like that in my organic
labs. of course the people who do those kinds of things are usually gone after the first 2 weeks or so.
[Edited on 22-3-2006 by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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The_Davster
A pnictogen
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I laughed pretty hard at the last one myself. But I have seen some stupid stuff in my time in the organic labs as well.
A couple examples:
Someone poured an ether extract into a vaccuum flask with the vaccuum line connected and running(aspirator was supposed to be used, not vaccuuum
line), she poured down the side of the flask and everything was sucked down the vacccuum line.
Someone put their hand over the buchner while vaccuum filtering, his hand got stuck and he jerked it upward and the sudden pressure change sent
product everywhere.
A girl was drying a testube by blowing compressed air in, and she for whatever reason had the rubber hose with compressed air right down the testtube
and she let go, it flew across the room.
The pipette bulbs seriously hold 50L of air! WOW. (we might not be thinking of
the same type of pipette bulb though)
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EtherBunny
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Oh, you won't believe the kind of stuff people do in organic labs. My personal favorite is when people hook up condensers to aspirators and Bunsen
burners to water lines.
I do research in organic synthesis, and a while back, when I was just starting out, I did something extremely dumb. I was making methylsuccinic acid,
following an ORGSYN protocol. Since it's made from ethyl crotonate, one of the steps is to dump the whole thing into nitric acid to oxidize out any
crotonate that may exist after previous step. Anyway, after I did the nitric acid step, I dissolved the whole works in benzene set it up to distill
off the benzene to dryness.
The distillation was going at a slow drip, and I decided it would be the perfect time to wash some glassware, when all of a sudden I heard a sound
that can best be described as "*BLAM*hissssssss." I looked over into the fumehood to see the entire inside of the setup charred and blackened, with a
disgusting grey smoke pouring out of the vacuum port. The temperature was well over 170C, the distillation flask had cracked, and the stopper in the
still head holding the thermometer had blown clean out, ejecting thermometer pieces clean out of the fumehood. I was still finding them two weeks
later.
Moral of the story: If it contains nitrates and nitrated benzenoids, don't be washing glassware.
One of my colleagues, doing a similar distillation, once managed to decompose some thionyl chloride which blew sulfury gas all over one side of the
lab and smelled like the worst fart ever. That was a nasty one to clean.
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mick
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Younger people 30 y ago were a lot more sensible
2) inflating a rubber pipet bulb with compressed air until explosion (impressive AND plain stupid) It can easily contains 50L of air.
The old red rubber pipette filler was well known to inflate with air and water.
From memory
Me and my friend, he was leaving, on a friday afternoon at work decided to see how much water this 25 ml pipette filler would hold. We were on works
water pressure of over 60 psi.
After a while the joke got serious.
The rules were
After filling the pipette filler with water you had to pour the water into a glass measuring cylinder and only what was in the cylinder counted.
The results were
After a slow start a 2 l cylinder was require.
I got passed 10 l with spillage. My friend was well past that but the pipette filler went before he could move it.
It was only water under pressure and everthing was wet.
mick
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Douchermann
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Haha, thats awesome mick.
I have a couple stories, all mine are pyro related though, I seem to work a lot safer in a lab environment.
1) My friend and I were up at his farm about a 5 hour drive or so from where we live. We were making smoke mix, and I gave him the KNO3 and sugar and
told him to go make about a pound of it. Well he goes back there, and I go back to my duty of making black powder (we made about 4 pounds of
granulated blackpowder that night). Now, this is the key part, I brought my gas stove up for him to use. The spoon he is using to stir falls into
the flame and catches. He panics and throws it into the pot with all the molten smoke mix. The whole batch catches. All I hear is a "oh shit", I
look back and see an 8+Ft flame coming from behind the back of the pickup truck (where he set up the propane stove). When the flame stops, I go back
to assess the dammage. The aluminum pot has a hole through it, the spoon is bent from the heat, there is black ash everywhere, and there is a heat
scar on the back of the pickup truck.
2) The same friend and I had a bag of KClO4:Al flashpowder laying around. Well his dad recently bought the parts to make a big steel mortar tube,
which we assembled. The mortar tube doesn't have a bottom yet, we were going to screw it into a peice of wood. My friend wanted a small fireball to
come out of this, so I told him to load up a bit of the flashpowder and I was going to go prepare a delay mechanism. The delay was a peice of a flare
core, delicately balanced on top of the tube. After it burned a certain ammount, it was supposed to fall in and ignite the flashpowder. I balance
it, and we run about 20 or so ft away. He says "here, take this" and throws me the bag of flashpowder. There is maybe a couple grams of flashpowder
left in here, and I remember making about 130 grams of it. All I say is "RUN!" He runs behind the garage, I run behind a different brick wall.
After the anticipation builds up as much as it could, I hear the loudest explosion I have ever heard in my life. I run back to where the pipe was and
all I see is a white/grey burn mark on the concrete where the pipe once stood. I look around for fragments for a short while, then a couple feet in
front of me, the pipe hits the ground. This was about a 20 pound pipe and it was airborn for nearly 10 seconds.
3) This one was completely my fault. I made a batch of negative-x for the day. Then I put it in my coat pocket and forgot about it while I was at my
friends house (same friend as the last two times). I fall asleep and drape the coat over my legs. Sometime during the night, the bag must have
opened and collected moisture from the air. At around 7am, I wake up to a bright fire. I look down and see a 2 ft flame coming from my legs. I jump
out of the bed and by then I realize what happend. My coat was completely ruined, and there is a big burn mark in my friends guest bed (which is in
his room also). Him, I, and the other kid that was over just laughed as we tried to hide the evidence from his mom... which we did successfully.
It\'s better to be pissed off than to be pissed on.
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EtherBunny
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I saw yet another case of complete idiocy the other day, and it's amazing how using the wrong apparatus can really cost you. Yet another colleague,
who is a dear friend but seems to be less organically inclined than some of are, was making some sort of acenapthene thing, a crucial intermediate for
her synthesis.
This stuff had to be vacuum-distilled (at around 0.2 mm Hg or so) so instead of using something more suited for high vacuum distillation, like a
short-path still head with a built-in Vigreux column, she sets up one of those great big multi-piece things with a huge condenser, and attempts to
hold her thermometer in the distilling head with a large rubber stopper, which is full of cracks.
When she turned on the vacuum and started heating it up, it took forever to distill because air was being pulled in through the stupid faulty stopper
and diminishing the vacuum. In the mean time, the air being pulled in with the distilling flask, combined with the high temperatures, oxidized her
product and within a few minutes, everything was burnt, pure carbon. After all was said and done, she ended up with a broken 1-L flask and no
acenapthene thing. The next day I threw away all of the rubber-stopper thermometer holders.
However, the most fantastical case of stupidity I have ever seen in my life was committed by none other than the PI. It was the true meaning of a
recrystallization gone really, really bad.
He was attempting to recrystallize a metric assload of napthylacetic acid from, I believe, water, where he had it all in a 4-L beaker, boiling on a
hot-plate set at full power, because that stuff was not going into solution. In his fumehood, he had another 4-L beaker, a 1-L beaker, a 2-L
separatory funnel, and an Allihn-style condenser about three feet long. The sep funnel was right next to the hot-plate, and, unfortunately, it
contained ether, which caught on fire.
I was on the other side of the bench doing something, and he yells "Oh shit!" I look over across the lab, and his entire fumehood is a roaring mass of
flame. No exaggerations, this was the Bibical burning of Sodom. All he could say was "That's not too good." His vacuum lines started melting, and he
charred the back of the hood real nicely, too. He ended up totaling his synthesis and destroying all of the glassware, (about six-hundred bucks worth,
we estimate) including the sep funnel, which was his wife's. Oops.
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Zinc
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Today I and my friend were playng with bromine in school. Our chem teacher allow us to work with any chemical we want axcept conc. acids but I don't
understand why she doesnt allow us to work with conc. acids if she allows us to work with bromine that is equally dangerous as most conc. acids.
Anyway, we poured around 10g to 20g of bromine in a baker, put a spoon ful of Al powder and covered the beaker with a watch glass. This was the first
time we were doing this experiment so we didn't know how violent the reaction is. So When the reaction started a huge cloud of a mixture of bromine
and aluminum bromide was evolved that filled almost the whole chemistry cabinet. Imediently we walked out of the cabinet. Fourtunatly the cabinet is
seperated from the classrom but some bromine and aluminum bromide did come in the classrom so the whole classrom was filled with the smell of bromine.
At the same time our classmate were writening a exam and some of them put shirts over their mouths and noses. Suprisingly our chem. teacher was not
wery mad at us.
[Edited on 25-5-2006 by Zinc]
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S-Bursic
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Actually, it wasn't 10g to 20g of bromine it was exactly between 12g and 15g.
Yes, I am the friend and we weren't playing with it, we were doing experiments.
We took a 100 ml flask and I poured in enough bromine to cover the bottom of the flask which was about 3 to 4ml of Br2.We put in one spoon (a very
small spoon) of Al powder and then we covered it with the watch glass and waited about ten sec. when the bromine started to come out . My opinion was that it was not properly covered, and that we put in too much
bromine for our first time with bromine. It was pure luck that I opened the windows before the experiment started . We came in about then minutes after and it was still pinching in the throat if you breathed.
Three days after and you can still smell bromine in my hair and my clothes(yes i washed them).
It was a very instructive lesson, although.
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Fleaker
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I know bromine well. Your first mistake was adding aluminum powder. It might take a little while to get off, but use aluminum foil Much safer than aluminum powder. Another thing to watch out for is not touching a
bromine bottle that has bromine on it. First it looks like you cut yourself (the blood red color sans fuming ), then it feels like it!
I did another foolish thing a while back, actually, while synthing bromine from NaBr. I added the sodium bromide to the 32% hydrogen peroxide
forgetting that halide ions *catalyze* the decomposition of H2O2. Silly me. Oddly, the 2L of peroxide were just fine carrying it up from the basement.
As soon as it reached the sunlight of the backyard...well, needless to say, it flash boiled and sprayed boiling hot peroxide onto my friend and I.
Not to mention the liters of oxygen and steam shooting out of the container!
[Edited on 25-5-2006 by Fleaker]
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