Author Topic: Your Really STUPID Lab Mistakes....  (Read 9606 times)

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ClearLight

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Your Really STUPID Lab Mistakes....
« on: November 05, 2002, 10:01:00 AM »

  Here, for the erudition of all, is where we get to post our favorite "DUH" lab mistakes...  thus we can learn and be entertained at the same time...


  1.)  My most repeatable one is pouring my solution into the sep funnel with the stop cock open... even better when I haven't put the beaker under it!

  2.) Shaking a mix of RP and KCl03 dry on a filter paper under the hood, which promptly ignited!

  3.)  Using the tlc reagent sprayer without setting the pressure gauge on the tank, and fogging the lab with a nice mist of HCL+Erlich's reagent, while not wearing a respirator!   :o



Infinite Radiant Light - THKRA

GC_MS

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used
« Reply #1 on: November 05, 2002, 10:09:00 AM »
1 - I used NaOH to acidify a solution of p-methoxyphenol (was after a long night of hot steamy sex, perfumed with a divine 2C-B trip).
2 - Accidentally used concentrated H2SO4 in the pinnacol rearrangement of methylenedioxypropanediol to MDP2P. All hail the formation of useless black tar  ::)  (after a long night of sexual failure, due to severe alcohol intoxication).

Ave Hive, synthetisandi te salutant!

b159510

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I'm sure this will be moved
« Reply #2 on: November 05, 2002, 10:35:00 AM »
but- Rinsed a beaker with acetone. The beaker had bromine residue in it.  8)

Grabbed a solution of sodium thiosulfate, thinking it was sodium bicarbonate, and briefly tried to neutralize an acidic solution. Very  8)

BTW, aqueous sodium thiosulfate is used for bromine burns.

Thankfully nobody was around to witness these incidents, and they happened in a fume hood. Still nasty though.
You don't fool me, Oilman

lab_bitch

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I have a venting system that bubbles any ...
« Reply #3 on: November 05, 2002, 11:10:00 AM »
I have a venting system that bubbles any methylamine smelling gas generated by the nitro amination through HCl.  There is an inline valve that can be used to open or close this vent.  A while back, one of my workers was running the reaction and forgot to open the valve.  After adding about half the nitro, the rxn setup began to leak at all the joints and it was obvious that pressure was building up.  Wanting to get a better look at what was going wrong, he leaned over the setup and examined it.  Before he knew it, the addition funnel on top of the setup shot up to the ceiling like a rocket and completely shattered.  This was followed by a geyser of mercury containing rxn mixture that subsequently landed on him and a worker standing behind him.  Frantically trying to get the mercury off, they both ran to the nearest bathroom, stripped down butt naked and both climbed into a shower that would have been a tight squeeze for just one of them (they are pretty big guys).  At this point, I come in to see what all of the commotion is about only to find one of them bending completely over and sticking his head under the faucet, while the other one stood directly behind him trying to get to the faucet as well.  You can probably figure out what was going through my mind at this point.  Horrified, I asked them what in fucking hell they were doing.  They quickly clarified the situation only to have me point out that there were actually two bathrooms in the house.  I bet that made them feel really good!  To this day, I still continue to make fun of them about that incident and they have never forgotten to open the valve again.  I guess the moral of this story is to think before you act (i.e. opening a valve; jumping butt naked into a shower with another guy when you could just go across the hall; walking into a bathroom where you here the shower running and two guys yelling at eachother)

Sunlight

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shaking a warm solution
« Reply #4 on: November 05, 2002, 11:38:00 AM »
Shaking a still warm solution to extract the amine in a sep funnel with DCM, more than a half was directly spitted.
Shaking "slightly" a flask with the magnet inside, the flask was broken and it had THF...
And many more...

yellium

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Dumping a small amount of NaH (used for drying) ...
« Reply #5 on: November 05, 2002, 12:52:00 PM »
Dumping a small amount of NaH (used for drying) in the same sink where I'd thrown away some ether washes. NaH starts fizzing, as it usually does when you destroy it with water. Then starts burning. No problem, was only a small bit, so it should be out in half a second. Instant *woosh* as the ether fumes ignite.  Got only a few small burns on my hands (and removed all the hair on my knuckles). Organic chem fires are *intense*.

(lessons learned:
-don't throw flammable solvents down the sink.
-destroy NaH in the proper way, by titrating with EtOH and then dissolving the ethoxide in water.)

When all you've got is a nailgun, every problem looks like a messiah...

PoohBearium

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Mistakes
« Reply #6 on: November 05, 2002, 02:55:00 PM »
1)Using a pyrex bowl that was not stovetop certified to boil off the water in the very final step of a perfect 20g pseudo/I/rP, that took weeks to prepare for, SWIP's very first dream (still recovered enough in a towel that was under the bowl to OD on...  ::) )

2)Assuming that a glass salt shaker would withstand the pressure of a 1g nano, when doing a sealed reaction.

3)Trying to cut corners (too many to list!!!)

PB

WARNING:The punishment for self-rating your posts is a slow and agonizing death!!!

Rhodium

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Lab-size Mushroom Cloud
« Reply #7 on: November 05, 2002, 04:42:00 PM »
Adding 10g LiAlH4 through a powder funnel in one portion to 250ml of wet washing THF (used by mistake instead of the anhydrous THF prepared for this particular occasion). To make it even funnier I used a single-neck RB flask, so that the massive amounts of instantaneously evolved hydrogen pushed the remaining fine dust (which was still in mid-air inside the funnel and flask) upwards, forming a mushroom cloud, covering all the lab benches and the floor with a thin grey carpet of quietly hissing LiAlH4 slowly reacting with the moisture in the air.

wacko_reaco

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6kg performic run going horrible
« Reply #8 on: November 05, 2002, 05:01:00 PM »
all the reactants were in the pilot vessel, the temperature being contain by turning the cooling water on and off, when the temperature stopped going past 32C i was curious as to why, realised the chuck on the overhead stirrer had come loose and stirring had stopped for god knows how long, so instead of cooling the system right down and beginning stirring very slowly i just re-tightened the chuck in a panic and turnt he stirrer back on full, two seconds later 20Ldcm, 20L performic acid and 6kg iso were all over me and i was doing the mad dash to the shower, cleaning up that ffucker took two days and three pairs of rubber soled shoes (dcm likes rubber)

wacka wacka wacka

Tyler_Durden

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h2o2
« Reply #9 on: November 05, 2002, 10:04:00 PM »
Misunderstood the labeling of H2O2 40 volume for 3 YEARS, until about a month ago - ARGH!!!!

Oakenfold, LSD, Sasha, Shrooms, Digweed, MDA/MDMA

Moriarty

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I have some rhymes for the house!
« Reply #10 on: November 06, 2002, 01:37:00 AM »
I.  When SWIM was fourteen (14) years old, an age at which all sorts of mischeif seems to occur in the human male, SWIM was making murcury fulminate Hg(ONC)2 which is a common primary explosive many at that age try to make (generally successfully, as it is an easy synthesis for a young chemist).  What can SWIM say, he was interested in chemistry, and explosives are a given for a boy that age.

Anyway, if SWIM's memory serves him well, and it might not since that was 12 to 14 years ago, the reaction looks something like this:

Hg + 2HNO3 -----> Hg(NO3)2 + H2 + NO2 + HNO3 (excess)

Hg(NO3)2 + C2H5OH + HNO3 -----> Hg(ONC)2 + 2CO2 + H2O

NOTICE: SWIM DIDN'T TAKE THE TIME TO BALENCE THIS EQUATION AND IS NOT EVEN SURE IF THOSE ARE THE CORRECT REACTION BYPRODUCTS.  THAT PORTION OF THE POST IS NOT IMPORTANT TO THE STORY!!!  BY THE WAY, SWIM's NOT PROVIDING INFORMATION ABOUT EXPLOSIVES THAT ARE NOT ALREADY KNOWN BY EVERY 12 YEAR OLD CHEM ENTHUSIAST.

Anyway, that experiment and the production of Cyclonite (CycloTrimethylenetrinitramine [sp?]), the secondary explosive in C-4 plastique explosives won him several felonies and caused him to lose interest in chemistry until just about a year ago.

Anyway, here's his big snafu.  When the reaction was really moving along in a glass jar of about 2 gallons it overflowed.  Oh course SWIM was smart.  He scaled up for an exothermic reaction!!!  He was doing whatever it is he did back then but diddn't notice.  To make a long story short, when he tried to lift the jar with the mercury fulminate in it he hadn't noticed that a great deal of this very volitile, shock-sensitive explosive had dried beneath the heavy glass tea jar with indented grooves on the bottom.  He tried to lift it and FLASH!!!  Yep, an explosion occurred.  He had glass everywhere.  He's lucky only a small amount actually made it's way out of the jar and dried or he'd be dead.  Anyway, thankfully the shock wasn't enough to set off the fulminate in the alcohol solution or half his garage would have had SWI-Moriarty splatterings all over it.

I don't know if this really fits in this forum but it was a definate lab mistake that cost him :-[ !

II.  SWIM aminated some ketone last year.  He came out with nothing.  He recalculated the amount of 5% NaOH solution he added to basify for his A/B extraction and realized that he didn't add enough to get the pH above 7, meaning he threw all his honey away.  Save everything until your finished bees, that mistake hurt SWIM in amazing ways (he needed the money)!

Who wants to play cops and dope fiends?

Cyrax

  • Guest
When you neutralize a NaHCO 3 or a K 2 CO 3 ...
« Reply #11 on: November 06, 2002, 03:39:00 AM »
When you neutralize a NaHCO3 or a K2CO3 solution with HCl, place the damned beaker in an ice bath and add the acid DROPWISE.  If you don't - like me once - the freaking solution will jump right out of the beaker in a kind of mini explosion (due to the evolution of CO2) ... 
It was quite spectacular ... a piece of the erlenmeyer was blown away and the carefully synthesised product was splattered all over me.

Chromic

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THF volcano
« Reply #12 on: November 06, 2002, 06:44:00 AM »
1) THF volcano when mixing H2O2, THF and radical initiator in hopes of making GBL.
2) accidentally making some volatile bromo-organic compound when brominating THF.
3) shattering pyrex pie plate on element (flying hot sharp glass fragments, ouch! that one hurt)

Then there were SWIC's days with gun powder & other flammables...

BlizzardofOzs

  • Guest
Assumption!!
« Reply #13 on: November 06, 2002, 04:15:00 PM »
Happened twice should have learned the first time. But you know us. (Shit, yeah right) Never, ever assume that someone helping or for that means getting in the way of the "expert" knows what ther doing. My(worst)example; SWIB's usual work about 330 g's already ph'd ready to drop (helper) say's they know what to do. SWIB's not looking and when he doe's notices massive fumes coming from the 4 litre vission. Helper dropped water and half of the fuel. SWIB pulled it off heat and helper lights torch and Coleman fumes don't fuck around. Boom!!! all gone. That Gary Coleman's a mean mother fucker that's why I don't play with him no more. 

Ohhh yeahhh,the "SPIN DR." is in!!!!

Sifty

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Salt Peter
« Reply #14 on: November 07, 2002, 12:55:00 AM »
When I was 12 I was trying to melt a mixture of 50% sucrose 50% sodium nitrate in order to make a slow burning smoke bomb.

I was melting it on a gas stove.

It promptly erupted with a 2 foot purple flame and sounded like a jet engine, spraying molten sugar all over the kitchen. The sugar melted the carpet (replaced), the counter tops (replaced), the ceiling (repainted), and the fucking metal fume hood thing over a stove! Talk about hot!

Not to mention, a neighbor saw the smoke from the prematurely ignited smoke bomb pouring out a window and called 911!

After speaking with a police officer and 4 firemen, my mother finally came home and kicked the SHIT out of me. I was grounded for years.

-Sifty

"...Come with us and leave your earth behind..." - Chem.Bros.

pHarmacist

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Duh!
« Reply #15 on: November 07, 2002, 04:44:00 AM »
Doing a reaction, workup and what not, finished, friend calls, wants to hang out, ok fine, "-should i clean it now or later, nah.. I'll stopper the RB with a glas stopper so it dosen't stink, then I'll do clenup when I get back.. yes", being impulsive I got back home  after several days, I still havent managed to get the stopper out, this was a year ago... way to go..

Never underestimate the power of retrosynthesis.

thethethe

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Lab Mistake
« Reply #16 on: November 07, 2002, 04:26:00 PM »
Always label your containers of clear liquid!!!

See:

Post 235232

(Rhodium: "Re: Tasting E freebase oil..", Chemistry Discourse)


TTT

Drug shortage is a worldwide problem with neighborhood solutions.

Ace99

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Mixing GBL and NaOH inside the glass bottle the ...
« Reply #17 on: November 08, 2002, 07:14:00 PM »
Mixing GBL and NaOH inside the glass bottle the GBL came in, inside a hotel room. Since it was large scale and going slow, someone put the lid on, and swirled it. It started boiling inside, pressure was building up. Someone tried to take the lid off to relieve pressure and it sprayed everywhere like shaking up a bottle of pop and opening it, except much stronger. There was a loud pop, and it was all over the ceiling and walls. It was only half reacted so there was this really greasy oily GBL coating, no matter how much tried to wash it it was still greasy. Just said "fuck it" and packed everything up and left the room disgusting. I wonder what the maid thought about the greasy stuff on the walls and mirrors and ceiling that just wouldn't come off.

Xicori

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when SWIM was a young stupid boy he tried his ...
« Reply #18 on: November 11, 2002, 06:23:00 AM »
when SWIM was a young stupid boy he tried his first amphetamine synthesis:
after the Benzaldehyde/EtNO2-Reaktion he wanted to remove the residual EtNO2 on the hotplate - his nitropropene burnt and the room was full of tear-gas-like vapours ... ::)

so swim learnt that it is important to use an oil bath and destillation setup :)

ChambeRed

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Unlabeled containers+pigsty lab+poor ...
« Reply #19 on: November 11, 2002, 10:06:00 AM »
Unlabeled containers+pigsty lab+poor memory=recipe for disaster!label those containers! ::) .

Bee's don't die,we just multiply.