Sciencemadness Discussion Board - When Chemistry Goes Wrong

When Chemistry Goes Wrong

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j_sum1 - 9-2-2016 at 22:14

JJay, what is your experience with pricechopper2011?
I came across his eBay listing recently. It looks the epitome of cheap Chinese junk. But, for low-use items, that might be all that is needed -- provided they actually function. I was looking at a short Liebig and have more-or-less made a decision about it, but, some actual information on the quality would be appreciated.

JJay - 9-2-2016 at 22:21

I bought a kit from him. The flasks are good ; the Liebig and sep funnel are good. The thermometer adapters are ok but inferior to Deschem's; the stoppers are fine. The 105 degree adapter, Claisen adapter, and Vigreux column all had very serious flaws. I haven't broken the Vigreux yet. I briefly considered buying his [pricechopper2011's] Claisen adapter because it is so cheap but his shipping is incredibly slow, and I don't feel like waiting, so I ordered something from the USA.

[Edited on 11-2-2016 by JJay]

The Volatile Chemist - 10-2-2016 at 08:46

Quote: Originally posted by Etaoin Shrdlu

Too acidic possibly? Try adding a little NaOH solution. Better an excess of alkali than acid here. Excess NaOH will be soluble anyway.

Hmm, thank you! I added Citric acid to a solution of barium hydroxide and got a precipitate, and so I wondered why this more recent attempt did not work. Thank you! I'll try that in a few hours.

Edit:
Ironically, with plans of fixing the reaction when I got home, I arrived to see a large mass of precipitate in my beaker. Success.

[Edited on 2-11-2016 by The Volatile Chemist]

XeonTheMGPony - 11-2-2016 at 15:10

Well not relating to a chemical reaction but today when cleaning my beakers I was drying one of my newest ones when it decided to shatter, my reward is a nice gaping 2 inch sub dermal laceration in my thumb (IE It cut the living shit out of my thumb) So I am essentially one handed for at min 1.5 weeks!!!

Thank goat I keep a ton of first aid gear on hand, makes for prompt treatment of such things, some thing I hope every one has on hand, it isn't all ways the chems that can sneak up and bite you!

JJay - 11-2-2016 at 16:03

Yesterday I was making some aluminum chloride right inside of an open garage door, and when subliming the last little bit, I heated the test tube a little too strongly, causing a huge cloud of aluminum chloride smoke to go streaming into the air. Unfortunately, the wind chose that moment to change direction, blowing into the garage. I ran for my respirator, and my lab partner ran away.

Next time I make aluminum chloride, I'll do it outside.

Herr Haber - 14-2-2016 at 03:27

You've read Urbanski on what industrial accidents used to happen "back in the days?" when making Nitrocellulose?

Well, lesson one: Dont work in a rush, even if you have a friend at home that would like to take home some of this NC.

I was actually trying to compare the différences in nitrating Cellulose both with 68% nitric acid and 92% nitric acid (home distilled). (Same amount of cellulose, same quantity of acids except the concentration).

The first accident happened because the temperature was to high (30c°) in the room and the nitric acid and sulphuric acid were at room temperature.
Maybe there were some organics in the cellulose too. Who knows... This ended with me and my gasmask on, extractor at full speed, window open and calling my friend: "Hey, if you wanna see what a runaway reaction looks like, now is the time. Just stop breathing". There was a beautiful column of NOx angling right where the intake of the extractor was

Yield was obviously low even though I caught the beaker with pincers and put in in ice.

The second accident happened shortly after finishing nitrating the cellulose with stronger acid (cold this time!). I drained most of the excess acid as I usually do and dumped the whole mass into a big sink full of cold water. As I had quality gloves and there were less than 10 grams of NC I put my hands Inside to press most of the acid out. Pretty much what you would do with a sponge. Sure, I felt the heat of the acid dissolving but it wasnt a concern.
The stupid move was to take the ball of wet with water and acids NC out of the water to squeeze it.
WHOOOOSH !
Some cotton burned on my labcoat, the gloves suffered a bit from the heat but fortunately I was still wearing my gas mask so no burnt eyerbrows or hair.
Of course, by that time, my friend who is not faint hearted was a bit concerned and I proceeded to cleanup.

So in one day I managed to:
- Provoke the most two common industrial accidents Urbanski mentioned.
- Etch into my brain that "accidents happen on the roads that you know best".

Lesson learned !

Starcruiser - 14-2-2016 at 04:05

Casting zinc in a plaster mold some couple of days ago withe the purpose of making an electrode for galvanization. Knowing that the mold should be dry, I`ve kept it for about 4 days on my room heating radiator.

The zinc easily melted in a tuna can on a propane burner. Pouring the molten metal into the mold... and, not really a big surprise, it started to boil (actually what boiled was the water from the not so dry mold) and splatter little beads of zinc all around. Beautiful but kind of dangerous. No harm done, but yesterday bought some leather welding gloves

For the next casting experiment (this time will do some lead) I`ve took the precaution to bake the mold in my kitchen oven for about 3 hours at 150 C.

Let`s see how this gonna go...

hissingnoise - 14-2-2016 at 04:35

Quote:

For the next casting experiment (this time will do some lead) I`ve took the precaution to bake the mold in my kitchen oven for about 3 hours at 150 C.

Lead's toxicity makes it hazardous ─ so a few further precautions are called for . . . ?

JJay - 14-2-2016 at 06:16

Today I heated a cheap test tube too strongly, and it broke. Then I tightened a clamp and crushed another one, at which point I decided to put the test tubes away for a while.

unionised - 14-2-2016 at 08:06

Quote: Originally posted by Starcruiser

Casting zinc in a plaster mold some couple of days ago withe the purpose of making an electrode for galvanization. Knowing that the mold should be dry, I`ve kept it for about 4 days on my room heating radiator.

The zinc easily melted in a tuna can on a propane burner. Pouring the molten metal into the mold... and, not really a big surprise, it started to boil (actually what boiled was the water from the not so dry mold) and splatter little beads of zinc all around. Beautiful but kind of dangerous. No harm done, but yesterday bought some leather welding gloves

For the next casting experiment (this time will do some lead) I`ve took the precaution to bake the mold in my kitchen oven for about 3 hours at 150 C.

Let`s see how this gonna go...

Do you know how paster works?
https://en.wikipedia.org/wiki/Plaster#Gypsum_plaster_.28plas...
When you pour hot metal into it you will dehydrate the gypsum and spatter metal everywher- again.
(I know, I've been there and done it )

Herr Haber - 14-2-2016 at 09:55

And that's why plaster is such a good fire retardant

(is that an English word?)

For that kind of moulds I'm Lucky enough to have a ceramics /glass maker suplier for hobbyists close to home.
Besides iron oxyde you wouldnt believe what chemicals they have there (copper compounds, lead, chromium, iron, manganese etc).
That and every kind of clay you could think of plus the other ones you didnt know existed. And they have all kinds of sieves too

And to stay on topic... today I was pouring some NaOH from a pot to a bottle. Guess who managed to get some extra beads in his gloves? :-/
Ouch!

MrMario - 20-2-2016 at 16:56

Yesterday I tried to dissolve Lead metal in Nitric acid. At first no reaction occured/tiny bubbles were formed, so i added more acid. When i was slowy heating the solution an exothermic reaction kicked in and large fumes of NO2 gas were evolved... It almost went outside the beaker, so i had to quickly act and put it in a large glass container. Inhaled very small amount of NO2 but throat still hurts a little. I'm never doing reactions with NO2 gas again..

blogfast25 - 20-2-2016 at 18:08

Quote: Originally posted by MrMario

Yesterday I tried to dissolve Lead metal in Nitric acid. At first no reaction occured/tiny bubbles were formed, so i added more acid. When i was slowy heating the solution an exothermic reaction kicked in and large fumes of NO2 gas were evolved... It almost went outside the beaker, so i had to quickly act and put it in a large glass container. Inhaled very small amount of NO2 but throat still hurts a little. I'm never doing reactions with NO2 gas again..

You just need to take precautions and think things through before you do them.

Oxidations with nitric acid have this tendency to kind of start all at once and then 'die' quickly, leading to a sudden rush of NO₂.

Do these things outside, with your back to the wind or in a decent fume hood.

You won't have suffered any lasting damage, just some transient discomfort...

[Edited on 21-2-2016 by blogfast25]

JJay - 21-2-2016 at 22:40

Today my 1000 mL beaker developed a star crack. It was my favorite beaker too. I'm not sure how it happened... I remember washing it after an experiment and not noticing any cracks. Then I sent it on a counter in a normal manner and walked into the next room to talk to a colleague. When I returned, I noticed that it was cracked.

Fortunately, an identical beaker was available on eBay, so my beakers will still nest with each other. (If you've never had one beaker that doesn't match... well... let's just say you're luckier than I am!)

The Volatile Chemist - 22-2-2016 at 16:42

Tried to pick a beaker of Chromium(VI) solution up with my fingers from an ice bath, and spilled it onto my fingers :/

Texium - 22-2-2016 at 17:58

Soak your fingers in some ascorbic acid solution for a few minutes and then wash them really well. That should take care of it painlessly.

MrMario - 23-2-2016 at 05:01

Quote: Originally posted by blogfast25

Quote: Originally posted by MrMario

I did do it outside, however i shouldn't have added all nitric acid on low heat when it did not react.. I still have a little sore throat and had a little fever, but i'm on recovery now

Btw, I searched the web for actively treating NO2 gas and converting it into something less dangerous but couldn't find any papers or medical publications. I did find that NO2 + NH3 will produce N2 gas and H2O, but does this happen at RT?

j_sum1 - 23-2-2016 at 17:10

Doing a trial run of a classic -- but one I have never actually done before: the reaction between sodium metal and chlorine gas.

To generate Cl2 gas I put some TCCA in the bottom of a flask and added some HCl.
The intent was to lower some sodium into the flask using a deflagrating spoon. Videos I had watched indicated that best results were obtained when the Na was molten first. For this purpose I had fashioned a glass spoon out of a test tube.

Problem was I accidentally smashed my spoon before starting. Short on time I grabbed a regular deflagrating spoon from the cupboard. The spoon itself was brass and it was riveted onto a steel wire.

Reaction proceeded well at first but I only had 10 seconds or so of actual reaction before the rivets melted out and the brass spoon with whatever sodium was left dropped to the bottom of the flask. No biggie, but sad to have the reaction cut short.

Reaction byproducts however were interesting. There was some reaction occurring with the brass spoon. After the flask had cooled a bit I filled the flask with water. There in the bottom was the nice purple of the copper-sodium dichloroiscyanurate complex. For a failure it was rather cool.

Magpie - 29-2-2016 at 08:48

For me this was "when chemical storage goes wrong."

A shelf failed in one of my two large storage closets. The shelf is supported by 4 pegs that plug into pre-drilled holes. A back peg came out for some unknown reason. Luckily nothing was damaged. I probably had 20 lbs weight on the shelf. This included 2 bottles of Everclear, 500 ml of nitric acid, a Wheaton stirrer, and a triple-beam Ohaus balance. So, my project for today is to beef-up the supports for those shelves.

szuko03 - 29-2-2016 at 09:48

Quote: Originally posted by Magpie

For me this was "when chemical storage goes wrong."

A shelf failed in one of my two large storage closets. The shelf is supported by 4 pegs that plug into pre-drilled holes. A back peg came out for some unknown reason. Luckily nothing was damaged. I probably had 20 lbs weight on the shelf. This included 2 bottles of Everclear, 500 ml of nitric acid, a Wheaton stirrer, and a triple-beam Ohaus balance. So, my project for today is to beef-up the supports for those shelves.

I am considering this to be a sign for me. It just so happens a few days ago I was cleaning out this tiny space to store pounds of compounds in, mostly oxidizers for fireworks so literally by the kilo (dont worry no fuels) but I am worried over time one of the shelves will fail and cause all 5 of the shelves to fail as kilos of things come crashing down onto other things...

Again because its like sealed bags of KNO3 and the alike nothing will actually break that doesnt mean i want go hear it from across the house and go "god i know what that was" Definitely know what i am doing with some spare time, thanks for the lesson!

[Edited on 29-2-2016 by szuko03]

Magpie - 1-3-2016 at 16:18

Here is my solution to the failed shelf support. This was for the cabinet that has primarily equipment. Next I will do an identical cabinet that has nothing but chemicals.

Great - 1-3-2016 at 20:15

Tried making Potassium (again) by electrolyzing Potassium Hydroxide in a copper endcap. Lots of crackling, but no visible metal. Tried mixing with Sodium Hydroxide to make eutectic mixture, barely worked, if even. Only tiny tiny grains of metal formed.

Tried making Aminoguanidine Bicarbonate, got 2 grams from 10 grams Cyanamide, which fucking sucks. I lost a lot during the Bicarbonate addition, as my product precipitated instantly, mixing with the Sodium salts and forming a slurry of shit.

Magpie - 2-3-2016 at 22:23

Quote: Originally posted by Magpie

Here is my solution to the failed shelf support. This was for the cabinet that has primarily equipment. Next I will do an identical cabinet that has nothing but chemicals.

update:

Today I emptied out the cabinet full of chemicals (dry and some low hazard liquids). Another shelf had lost a support peg! :mad:

CharlieA - 3-3-2016 at 06:06

update:

Today I emptied out the cabinet full of chemicals (dry and some low hazard liquids). Another shelf had lost a support peg! :mad:

[/rquote]

If that won't hold up now, nothing will!

aga - 28-3-2016 at 12:17

Who needs to wear eye protection when doing seemingly simple and menial lab tasks ?

Well, me, you, everybody, always !

Picked up a plastic beaker of copper sulphate that had been hiding at the back of the fume hood for about a year.

Looked all dried up so i crushed the beaker to release the crystals from the sides.

They exploded upwards, resulting in some tiny copper sulphate crystals in my left eye.

Wash bottle, squirty-squirt-long-time and it is still irritated an hour or so after being hit.
(yes, i checked the wash bottle to make sure it was actually DIW in there).

Fact is, goggles MUST be worn at ALL times in a lab environment, or, at best, your left eye will itch for hours and hours.

At worst, neither eye will itch, as they will both be Gone, then you'll see (!)

Here endeth today's lesson by Learning Through Stupidity<sup>tm</sup>

gatosgr - 29-3-2016 at 09:55

Wear gloves, chemicals can get through your skins and make you crazy.

JJay - 29-3-2016 at 11:00

I had a huge comedy of errors with my tube furnace.

I was having some problems with my power supply, so for troubleshooting purposes, I connected the furnace directly to the wall current. The heating element burned out in about 10 seconds.

Then I rebuilt it twice using a different brand of refractory paper, one that apparently conducts electricity better than expected. Both times it failed at fairly low temperatures.

Then I tried building one out of perlite cemented with sodium silicate. Unfortunately, that composition melts at well under 1000 C, and when molten it etches quartz. So now one of my quartz tubes is damaged (though still serviceable)....

I built one out of stoneware clay last night, and so far it seems to be working OK, but it's going to require some insulation....

[Edited on 29-3-2016 by JJay]

ave369 - 29-3-2016 at 11:28

Quote: Originally posted by gatosgr

Wear gloves, chemicals can get through your skins and make you crazy.

You have to work with very specific chemicals to end up crazy (as opposed to burned, sick, ill or dead). And if you work with them, you have bigger problems than lab safety. Problems such as the local law.

aga - 29-3-2016 at 12:15

Quote: Originally posted by gatosgr

... through your skins ...

That's Alien Lizard talk right there.

Daffodile - 29-3-2016 at 20:21

Quote: Originally posted by aga

Quote: Originally posted by gatosgr

... through your skins ...

That's Alien Lizard talk right there.

Damn reptilians eh. I know what you mean. Whenever I see a really hot chick on the bus, I gotta just accept that she's a disguised reptilian lizard, and that its not worth thinking about my chances.

This board looks more like 4chan every day.

Alkoxide - 29-3-2016 at 20:56

My biggest mishap came in organic lab I two years ago. I don't remember what the lab was, but I do remember we were working with a bunch of carcinogenic stuff, pretty sure dichloromethane was in the lab. My lab partner and I had performed several small reactions in test tubes and we were instructed by our TA's to dump everything from our hood into the big 4L waste bottle in the far hood in the lab. When it came time to clean up, I poured all the test tubes into a single beaker to dump in the waste bottle and a 2 foot geyser of liquid cancer shot up from the beaker and sprayed my forearms (hands were safe from gloves). I quickly washed off my arms after (luckily I didn't seem to have any chemical burns). Apparently the TA's didn't know that they should have prepared individual waste bottles for each reaction we had to perform and that the different reaction products were incompatible. Lesson learned, double check the TA's.

[Edited on 30-3-2016 by Alkoxide]

gatosgr - 30-3-2016 at 08:36

Damn trolls...

[Edited on 30-3-2016 by gatosgr]

The Volatile Chemist - 1-4-2016 at 15:06

Yesterday I was trying to ignite a balloon filled with some hydrogen, but I couldn't get it to go off. Turns out a tiny flame from burning the string soaked in acetone won't pop a 1/4 filled balloon...

Intergalactic_Captain - 3-4-2016 at 14:12

Quote: Originally posted by Herr Haber

You've read Urbanski on what industrial accidents used to happen "back in the days?" when making Nitrocellulose?

Well, lesson one: Dont work in a rush, even if you have a friend at home that would like to take home some of this NC.

I was actually trying to compare the différences in nitrating Cellulose both with 68% nitric acid and 92% nitric acid (home distilled). (Same amount of cellulose, same quantity of acids except the concentration).

The first accident happened because the temperature was to high (30c°) in the room and the nitric acid and sulphuric acid were at room temperature.
Maybe there were some organics in the cellulose too. Who knows... This ended with me and my gasmask on, extractor at full speed, window open and calling my friend: "Hey, if you wanna see what a runaway reaction looks like, now is the time. Just stop breathing". There was a beautiful column of NOx angling right where the intake of the extractor was

Sounds like an incident I had when I was still messing with HE's. Had made a few small batches of nitrocellulose via H2SO4/NH4NO3, and this was the process refinement batch, IIRC something like ~30g. Smooth nitration, washed until neutral with NaHCO3, rinsed and laid out to dry.

This was before I learned to wash my nitroesters with urea to neutralize any residual NOx, and when I still dried solids with a 100w lamp/fan combination. I was also somewhere around 14 and had that teenage invincibility complex thing going strong.

You can probably see where this is going. It's sunday night, I'm watching TV with my dad, and suddenly there is a large bang - I fly off the couch, run up to my room, and find the door shut - I always left it half open for the cats - open it, and see nothing amiss, odd. . go to where the NC was drying, and find a couple grams worth of smoldering scraps and a ~6" diameter mangled "hole" that used to be carpeted - Over the next several months I found the rest of the pieces of the tray the NC was on. So, I go back downstairs and pretend that nothing happened, fully expecting the worst - Not a word, and to this day we don't bring it up.

Lesson learned? More than I can begin to consider - But at the time, all I could think of was stabilization of nitroesters, since now I had to do it again to replace what was lost. Holy fucking misplaced priorities. . .

aga - 3-4-2016 at 14:46

Quote: Originally posted by The Volatile Chemist

Yesterday I was trying to ignite a balloon filled with some hydrogen, but I couldn't get it to go off. Turns out a tiny flame from burning the string soaked in acetone won't pop a 1/4 filled balloon...

Put the string Around the balloon, not up through the hole where you put the gas in ...

100PercentChemistry - 3-4-2016 at 16:51

I was heating up a beaker and it broke. Luckily it was just sodium acetate. It did leak into my hotplate but nothing broke. I never have broken a beaker by heat before and it wasn't rapidly cooled.

CharlieA - 3-4-2016 at 17:45

Quote: Originally posted by 100PercentChemistry

I was heating up a beaker and it broke. Luckily it was just sodium acetate. It did leak into my hotplate but nothing broke. I never have broken a beaker by heat before and it wasn't rapidly cooled.

Could the beaker have been cracked? I'm thinking that maybe there was a small "star" crack.

JJay - 7-4-2016 at 17:02

Today I was making some calcium carbonate. I dissolved 800 grams of sodium bicarbonate in 8L of water in a 20L bucket and then dissolved 700 grams of calcium chloride monohydrate in 1.5L water in an 8L bucket. Then I started pouring the calcium chloride into the bicarbonate, completely forgetting about the carbon dioxide gas that would be given off. This resulted in chalk on the floor, which I cleaned up with vinegar.

Cou - 7-4-2016 at 17:48

I was doing the standard procedure to smell esters if you don't have the necessary apparatus to reflux and purify. I poured the reaction mixture in a plastic cup, and learned the hard way that esters dissolve polystrene. The oily ester layer on top ate a ring through the cup, made the bottom fall off.

j_sum1 - 7-4-2016 at 18:05

Quote: Originally posted by Cou

I was doing the standard procedure to smell esters if you don't have the necessary apparatus to reflux and purify. I poured the reaction mixture in a plastic cup, and learned the hard way that esters dissolve polystrene. The oily ester layer on top ate a ring through the cup, made the bottom fall off.

Well, I laughed!

MHN

Keith Fletcher - 7-4-2016 at 19:26

I heated up a 200 mg sample of Mannitol Hexanitrate in a steel measuring cup to see it melt and decompose and the instant I saw NO2 come off it detonated about 6 inches from my face and made my ears ring for a few hours. Didn't were a face shield or earplugs like a moron. I wasn't injured. Just absolute stupidity that should have been avoided.

Fegie - 8-4-2016 at 11:03

First major fuck up i ever did was when i disposed of my first batch of chloroacetone by pouring in a load of sodium hydroxide, and i was using a thin necked 500 ml flask, so everything shot upwards in a second or two after addition of lye...
Thankfully i had my face mask on and didnt burn my face...
After that i stopped using thin necked flasks with exothermic reactions.

JJay - 8-4-2016 at 11:09

Quote: Originally posted by Fegie

First major fuck up i ever did was when i disposed of my first batch of chloroacetone by pouring in a load of sodium hydroxide, and i was using a thin necked 500 ml flask, so everything shot upwards in a second or two after addition of lye...
Thankfully i had my face mask on and didnt burn my face...
After that i stopped using thin necked flasks with exothermic reactions.

Yesterday was the first time I ever had a runaway in a 20L bucket... of course, the reactants were rather benign. I can't imagine what lye and chloroacetone shooting out of a flask must be like... horribly corrosive, toxic, and burning. Must have been a nasty cleanup....

NeonPulse - 9-4-2016 at 00:45

Quote: Originally posted by Keith Fletcher

I heated up a 200 mg sample of Mannitol Hexanitrate in a steel measuring cup to see it melt and decompose and the instant I saw NO2 come off it detonated about 6 inches from my face and made my ears ring for a few hours. Didn't were a face shield or earplugs like a moron. I wasn't injured. Just absolute stupidity that should have been avoided.

MHN is a strange material bordering on the line of a primary. A lot of times it may just melt and puff like gun cotton but the rest of the time il will detonate. You probably would have been safe if was far less than 200mg./

Fegie - 9-4-2016 at 13:48

Quote: Originally posted by JJay

Quote: Originally posted by Fegie

I always do all my first experiments outside on pavement area that i treat with army grade chemical cleanup washing powder(no idea what it contains, i bought 10Kg of it for 5 euros from a surplus store, but it works wonders with acids and alkalines...) and wash afterwards if any spills occur.

Cleanup was pretty easy but the pavement area was left with a permanent faint etch, it has been there throughout the winter and summer...

Living in the middle of the woods is a good thing, nobody will complain about the terrible smell or noise...

The Volatile Chemist - 9-4-2016 at 17:25

Today I attempted to dry some sodium nitrate I had made, but there wasn't quite enough water in it to out my hot plate on 3 and expect it to dry out, so it splattered a bit. Got some on my lab computer's screen...

Yesterday I tried to grow a large crystal of copper(II) sulfate 5H₂O with a seed and a supersaturated solution of copper(II) sulfate, only to find out the solution wasn't quite saturated...

But on a better note I did eventually make a larger crystal, and successfully dissolved some Tin solder.

aga - 15-4-2016 at 10:45

Today i performed the classic Dumfuk Reaction (Tos, Pot, Richard Head et al 2016) of trying to distill Nitric acid using boiling chips

It became a lively NO₂ generator and boiling chip remover.

[Edited on 15-4-2016 by aga]

The Volatile Chemist - 15-4-2016 at 15:27

Quote: Originally posted by aga

Today i performed the classic Dumfuk Reaction (Tos, Pot, Richard Head et al 2016) of trying to distill Nitric acid using boiling chips

It became a lively NO₂ generator and boiling chip remover.

[Edited on 15-4-2016 by aga]

Lol

Turns out home-spun boiling chips aren't as great as cracked up to be (or any for that matter...).

WGTR - 15-4-2016 at 17:15

My latest frustration in the lab: I was trying to produce glyoxal from alcohol. Since mixing nitric acid with ethanol can turn into an "exciting" oxidative experience, it took me a while to feel comfortable scaling the reaction up to 20mL.

The oxidation seemed to have carried along OK. I neutralized the solution with CaCO₃, and then evaporated the mixture down. The copper catalyst seemed to have colored the mixture of salts a bit. I figured, "Hey, the procedure recommends extracting the glyoxal with ethanol, but calcium nitrate is soluble in it. I'm going to try acetone instead".

I did the extraction, and then evaporated the acetone away on the hot plate. I finished off the last bits of solvent in the vacuum chamber. What I ended up with was something that looked like a few mL of green snot. I poked it dubiously with a spatula, and it stretched away reluctantly as I pulled the spatula out. "OK, so glyoxal has been described as a thick, syrupy liquid..."

I did a Tollen's test with some of the goop, and the result came back negative.

Aaaarrrrgggggh!!!!!! I added a bit of dextrose to check my sanity...and got an instant silver mirror. Yaaarrrrgggh!!!!!!

I decided to bring out "My Precious", an unopened, small, 30mL glass bottle of glyoxal that I bought on eBay a year ago, just for lab emergencies like this. I cautiously pipetted some of the yellow looking liquid out, and performed another Tollen's test. Negative!!!!!??????? Aaaaarrrgh!!!!! *@&#^!!!!!

The little bits of "glyoxal" that I added to the beaker floated on top like a sample of motor oil. Hmmm... the CAS# said that it was 40% glyoxal. The label said "GLYOXAL" in big, bold, letters. Sigh...maybe it was the trimer. But how the heck was it lighter than water??? I boiled a sample of it in water, and it would not dissolve at all. The little oily globule floated there, mocking me. I blasted it in the ultrasonic tank, and made a milky suspension. When I took it out, the solution cleared back up into its neat little oily drop.

I added acetone to it, and then it was like, "Oh, you mean you wanted me to dissolve? OK!!! Sure!!!!" I have no idea what exactly is in that bottle, but it looks like light machining oil or something. I'm quite annoyed about that.

I went back and did the procedure again, but with too much alcohol, and not good enough reflux. I think I did actually end up with some glyoxal that time, but not very much. It gave a strong positive for the Tollen's test. I went back and took some of the precipitated salts (mostly glyoxylate and glycolate), and they also gave a positive result. Then I remembered that glyoxylic acid also has an aldehyde group. At this point, the results are inconclusive. Glyoxal is hard to purify, because it can't be separated by distillation. It forms a polymer that is very non-volatile.

So there was my latest batch of lab frustrations.

Chemist_Cup_Noodles - 19-4-2016 at 05:29

Quote: Originally posted by WGTR

My latest frustration in the lab: I was trying to produce glyoxal from alcohol. Since mixing nitric acid with ethanol can turn into an "exciting" oxidative experience, it took me a while to feel comfortable scaling the reaction up to 20mL.

I did a Tollen's test with some of the goop, and the result came back negative.

I decided to bring out "My Precious", an unopened, small, 30mL glass bottle of glyoxal that I bought on eBay a year ago, just for lab emergencies like this. I cautiously pipetted some of the yellow looking liquid out, and performed another Tollen's test. Negative!!!!!??????? Aaaaarrrgh!!!!! *@&#^!!!!!

The little bits of "glyoxal" that I added to the beaker floated on top like a sample of motor oil. Hmmm... the CAS# said that it was 40% glyoxal. The label said "GLYOXAL" in big, bold, letters. Sigh...maybe it was the trimer. But how the heck was it lighter than water??? I boiled a sample of it in water, and it would not dissolve at all. The little oily globule floated there, mocking me. I blasted it in the ultrasonic tank, and made a milky suspension. When I took it out, the solution cleared back up into its neat little oily drop.

I added acetone to it, and then it was like, "Oh, you mean you wanted me to dissolve? OK!!! Sure!!!!" I have no idea what exactly is in that bottle, but it looks like light machining oil or something. I'm quite annoyed about that.

I went back and did the procedure again, but with too much alcohol, and not good enough reflux. I think I did actually end up with some glyoxal that time, but not very much. It gave a strong positive for the Tollen's test. I went back and took some of the precipitated salts (mostly glyoxylate and glycolate), and they also gave a positive result. Then I remembered that glyoxylic acid also has an aldehyde group. At this point, the results are inconclusive. Glyoxal is hard to purify, because it can't be separated by distillation. It forms a polymer that is very non-volatile.

So there was my latest batch of lab frustrations.

Damn that just sounds like one shit day in the lab. Oh well, it happens. How long have you had this bottle though? Has it been exposed to a lot of light? I wouldn't think it would have any effect but maybe an oligomer formed if it sat there in the light forever. Maybe it's just a shitty Chinese product. Maybe you could try to find a better route to glyoxal. Try starting with a high purity acetoaldehyde and oxidize that perhaps. Good luck though, this compound seems awfully tricky for being just the most basic dialdehyde.

The Volatile Chemist - 30-4-2016 at 08:53

Yesterday I tried to condense a solution of stannous chloride in HCl, forgetting there was still a good bit of HCl left...Got a good cloud of HCl before I caught my mistake...

aga - 26-6-2016 at 07:29

Today a 'simpler' synthesis of sodium nitrite using CaSO₃ and NaNO₃.

It sounded stupid because CaSO₃ doesn't dissolve in water.

It is stupid - doesn't work at all.

Dump the results, then on to boiling down some ferric chloride.

Hmm. It's a bit bumpy. Best let it cool a bit and add a stirbar.

splash.JPG - 96kB

Maybe add a stirbar earlier next time, right after repainting the new 'hood, including the ceiling.

Sulaiman - 26-6-2016 at 16:10

well, the SM badge survived, and you've "baptised" your new 'hood,
now photo's will look like they are from a true experimentalist, which you are .
I don't trust clean fume hoods.

Imagine the mess if you hadn't got the 'hood working

EDIT: maybe some extra splash-guarding for the ac plug/socket ?

[Edited on 27-6-2016 by Sulaiman]

The Volatile Chemist - 26-6-2016 at 19:18

Ouch...

Today I just *could not* get a 'pulver' from what chemicals I had to burn. Did various AN/sucrose mixes, tried to melt some into a paste and ended up with charcoal that looked like chocolate. At least I know the Maillard reaction works with sugar and ammonium nitrate... Big I think everything I tried was just too wet, I couldn't grind the AN enough, or I didn't have a proper way to ignite the junk. Was trying to use a match. It was also very humid. Whatever. Might try Ammonpulver tomorrow, but I don't know how I'll get it to ignite.

Procrastinium - 20-9-2016 at 21:39

To add my contribution to this beautiful thread, a friend and I decided to melt some copper using an arc furnace constructed from a refractory brick and an arc welder. Having succeed in producing a glowing red puddle of copper, we the attempted the most moronic experiment we could devise: we poured it into a bucket of water.

I estimate we had about 20 grams of molten copper (mp = 1085C) and on contact with water, a steam explosion of such magnitude occurred that the 20L bucket was ruptured. The sound was akin to that of setting off a milk bottle of hydroxy gas. On reviewing the video footage, most of the copper was blasted vertically up, but lucky we were wearing welding gloves and masks anyway. Occasionally I still find splatters of copper around the place.

NitratedKittens - 28-12-2016 at 06:08

Quote: Originally posted by aga

Real life example Cou or 38 Mol of aga breath will bathe you as you sleep.

Wow, thats 912dm3/liters of beer breath at RTP, but what is the concentration of EtOH.

JJay - 1-1-2017 at 08:40

I recently discovered that my overhead stirrer, which I bought used, had a crooked chuck. I followed the instructions in several YouTube videos on how to remove chucks, using a hammer and an Allen wrench... unfortunately, the chuck turned out to be a collet chuck with a bent shaft, and in hammering on it, I managed to crumble part of the vinyl worm gear on the shaft. It will still run if I put it back together, but now it doesn't run smoothly *or* have a straight chuck. So it looks like I'll be calling the American office of the Japanese manufacturer to see if they'll sell me a shaft and a new worm gear... I have a feeling this is going to cost a lot of money....

TheNerdyFarmer - 1-1-2017 at 18:17

I have a couple actually.

1. Not that bad but could have been. I was new at chemistry and was attempting to make sodium silicate. Pretty straight forward synthesis, but instead of using borosilicate glass I decided to use a soda glass vial long story short the glass ended up breaking and unreacted sodium hydroxide got everywhere on my workbench... Use proper glassware.

2.Probably my worst accident. Also new to chemistry (not long after the previous accident) I decided to attempt the synthesis of nitric acid. Little bit more dangerous than sodium silicate. I had finally gotten all of my equipment and chemicals together to make it and so I mixed them. Not much was happening so I grew impatient and simply left to do something else. When I came back the stopper had popped off of my vacuum flask and there was hydrochloric acid everywhere not to mention the toxic gasses that where released in my shed. What happened is I forgot to dilute the HCl and when I left the reaction took place and it happened fast. More gas was being produced than gas being released thus leading to the stopper coming off aswell as the contents of the flask spewing everywhere. But in the end I did in fact make the nitric acid

. Moral of the story is always follow directions closely if your new and don't try and speed reactions up by adding more chemical to the mixture.

Edit: Also it completely destroyed my hotplate and actually managed to trip a breaker that powered the shed. When the chemicals got under the surface of the hotplate it must have brought many wires in contact with each other causing lots of sparks and a tripped breaker.

[Edited on 2-1-2017 by TheNerdyFarmer]

Geocachmaster - 1-1-2017 at 18:50

Recent: Attempting to make hydrochloric acid via sodium bisulfate and chloride. My hotplate is probably hot enough but I added some water anyway to help HCl being driven off (this was the problem). I usually do stuff like this outside but it was raining and I figured with the inverted funnel trap I'd be okay. After a few minutes of heating up the reaction mixture started bubbling and the HCl starting bubbling through the water in my receiving flask. This all works for about 10 seconds until water that condensed in the tubing runs back towards the flask. It leaks out of the tubing connection and starts dripping on the hot plate, instantly vaporizing and putting HCl into the room. As this is happening the flask on the hot plate, now too hot to hold, starts bubbling out of control. The panic as you rush to find tongs as HCl is coming into the room... Complete failure and only .05 M acid was the result

A while ago: It was about 18 months ago when I started getting interested in chemistry. I spent around $200 on basic glassware and chemicals, which included some 98% sulfuric acid and potassium permagnante. Being stupid and unaware of risk, my first idea was to prepare manganese heptoxide

. I then went on to make some (without any research other than NileRed's video) wearing shorts, a tee-shirt, BARE FEET, and NO SAFTEY GLASSES (makes me sick thinking about it). A garden hose was my only safety. It was going so well, until disaster struck. I was having fun dipping some paper towel in and watching it burst into flames seconds later. I had just dipped some paper in when a mosquito landed on my arm. I swatted at the mosquito with the manganese heptoxide SOAKED paper. An area of skin of ~2Cm squared got a nice bit of the chemical on it, along with the excess sulfuric acid. It instantly burned and ran to the hose. I sprayed it with water after for about 10 minutes before I decided that was enough water. I then thought I should dispose of the rest before something else went wrong. I dropped the container holding it into some water and it splattered getting a bunch on my arm. Some more hosing down and a shower later and I was okay except for few raw wounds on my arm. To this day I still get scared thinking about how close I came to getting some in my eyes when it splattered and how I would have very probably gone blind. That scared me into wearing safety goggles always, so maybe it wasn't all bad?

[Edited on 1/2/2017 by Geocachmaster]

JJay - 16-1-2017 at 22:50

Today I tried extracting around 700 mL of solution with 30 mL of ether, only to see the organic layer disappear with shaking. I added my other 30 mL of ether, all that I had on hand, to see a tiny organic layer form. Unfortunately, it didn't appear to contain much of the product.

charley1957 - 22-1-2017 at 19:12

My greatest mishap was when I was about ten years old. Was melting lead tire weights to make fishing weights with on a wood fire out in the yard. For some dumb reason I decided I needed to cool the pipe cap I was using as a form for the weights. Without drying it I made another pour, standing right over it. The small steam explosion sent molten lead all over my face, ears and scalp. VERY lucky I didn't lose my sight. Lucky too I didn't drop the crucible on my feet when I dropped it, pouring molten lead all over. I still have the scars on my cheek, near the inside corner of one eye and on my ear and forehead, and that was 50 years ago this year. Oh, the stupidity of youth. A very significant amount of money has gone into goggles, respirators, face shields, gloves of various kinds and other personal protective equipment for my lab. I never forgot that instant bewilderment at how incredibly quickly something so unexpected could happen.

Geocachmaster - 5-2-2017 at 18:08

Uhg... Remind me not to fill the flask more than halfway, especially when a lot of gas is going to be given off...

Why I filled it all the way, I'll never know.

JJay - 5-2-2017 at 19:47

Never, ever wash your mercury thermometer in cold water when the temperature on it reads in excess of 300 C.

woelen - 6-2-2017 at 00:40

A little disaster occurred in my lab. I had a big plastic container full of calcium hypochlorite (swimming pool shock treatment). Last few weeks I have been very busy with studies and hence I did not open the big cupboard in my lab. In the meantime, the plastic of the bottle became brittle and fell apart, exposing the calcium hypochlorite to the air in the cupboard. The chlorine coming from this hypochlorite has destroyed many things in my cubboard. Now, looking back, I can explain the faint chlorine smell in my lab of the last weeks.
Appr. EUR 500 worth of electronics is corroded (e.g. a router with green oxidized stuff on all its connectors, a completely rusted power supply, high voltage capacitors (5000V / 40uF) with completely corroded screw-connectors, the outside of the big capacitors rusting like hell and full of blisters, labels of other chemical bottles bleached out and very humid, LEDs, resistors, transistors, inductors, all I have to throw away, they are completely useless, a pressurized can of WD-40 lubricant broken open and its contents leaked out of it, making a puddle of oil, another pressurized canister with so-called dust-off was rusted and empty. The cupboard itself also is destroyed inside. All hinges and metal parts are severely corroded, the plastic, covering the hardboard has blisters all over and feels wet. The iron parts are wet, covered by a mix of rust and wet stuff (probably completely liquefied iron(III) chloride). I estimate total cost of damage to be around EUR 1000

So, never store calcium hypochlorite in its original container for more than a year. The container may look sturdy, but the slowly released chlorine and hypochlorous acid vapor slowly make the plastic brittle and then it simply cracks under the weight of its contents. I had the calcium hypochlorite standing there for nearly two years and only had used 100 grams or so of it. The remaining nearly 1 kg can do a LOT of damage by all the fumes it gives off.

Bezaleel - 6-2-2017 at 07:52

Ouch!!! Thanks for the warning.
I had unintended corrosion when I kept plastic bottles containing 36% HCl and 52% HNO3. Labels wet and unreadable, chromed hinges of the cupboard rusting, white crusts everywhere, and everything that stood in the cupboard felt moist and dirty. Since your advice for red capped glass lab bottles, this is virtually over.

fluorescence - 6-2-2017 at 09:15

We tried to de-gas Methanol for a reaction in the lab. For non-polar solvents like Hexane you simply freeze them in liquid Nitrogen, then let them melt again under high vacuum so the gases are removed and then freeze it again, like 4 times.

However you shouldn't do this with Methanol....as I was told too late unfortunately. Apparently it will either go into small cracks in the glass or the functional group (OH) might have interactions with the polar functions in glass. If you let this melt the normal way, even under high vacuum the flask will explode like ours....one way to avoid it would be to heat the flask for some seconds so the "ice-block" looses contact to the glass wall.

I guess it's more like Methanol might expand a little and destroy the flask that way...it doesn't matter why it happens just keep in mind that rapid melting of frozen polar solvents can be dangerous for glass....

Geocachmaster - 11-2-2017 at 14:44

I just wanted to use my shiny new Soxhlet extractor. I though maybe esterification with drying agent in the extractor like Nurdrage. 20 Minutes into reflux for making ethyl salicylate the siphon tube activates. What was left of the reaction mixture had a significant amount of ethyl salicylate and was boiling at much higher than 78. The ethanol pouring back in boils on contact and spews a bunch out the top of the condenser. The wintergreen smell was so strong it was hard to breathe

. I really need to build a fume hood.

MeshPL - 12-2-2017 at 05:46

I guess you need to use a smaller extractor or a larger excess of ethanol or do the reaction on largere scale with the same extractor to prevent such an occurence.

This is I an example where the reaction literally failed because the scale was too small... compared to the size of extractor. A smaller extractor wouldn't hold all the ethanol from ester mixture which would still boil at ca. 78C. A larger excess of ethanol couldn't fill the extractor and without remaining in a reaction mixture. A larger scale is an equivalent of making the extractor smaller.

A Halogenated Substance - 12-2-2017 at 06:54

I created some videos (using "lovely" text to speech) about my home chemistry mistakes during my first year of amateur chemistry. Some of these weren't really accidents and were instead very "potential" for accidents. Some of them are quite horrifying to me today.
I'm very surprised I was not injured more often back then.

https://www.youtube.com/watch?v=s-LFxh_ghLc

https://www.youtube.com/watch?v=jKt4IB4U7dw

Enjoy my early ignorance.

Edit: There's also a "first bromine distillation" video somewhere on the channel. It's already mentioned in the videos I linked above but if you're interested in it here's a more detailed video over it...

https://www.youtube.com/watch?v=F7k_svSp71o

[Edited on 2-12-2017 by A Halogenated Substance]

Rhodanide - 15-2-2017 at 06:36

When chem goes wrong?
I know a bit about that.
Spilled Chloropicrin on myself, 35mLs.
Thank holy **** I was wearing an EXTREMELY hydrophobic FBCS. (Full-body Chem suit)

Melgar - 23-2-2017 at 13:02

Trying to dissolve palladium in aqua regia, and wanted to make sure that it had dissolved as much as possible, so as to minimize fumes during evaporation. Put a torch flame directly on the beaker. Not full-blast or direct, but still enough of a thermal gradient that I now have $400 worth of palladium salts soaked into my carpet and a few other casualties that got in the line of fire. Interestingly, when I started using an ozone generator in that room to reduce odors, the polyester carpet gradually disintegrated in the areas where palladium salts had been spilled.

Sulaiman - 23-2-2017 at 14:15

if a replacement carpet costs around $400 might it be worth buying a nice new carpet and processing the old one to recover the palladium ?

JJay - 23-2-2017 at 20:02

I personally hate the smell of ozone; for me, that would be like keeping a pet skunk to mask unpleasant cat odors.

That is interesting, though... I guess it is a catalytic oxidation? Hopefully it isn't generating carbon monoxide.

Tin man - 23-2-2017 at 20:38

This was a few years ago, before I really got into chemistry. So I had been cooking rocket candy( 60/40 mix of KNO3 and sucrose) for a while at this point, and I was quit confident on my abilities to melt the mixture over an open wood fire without the possibility of spontaneous ignition, and it was working great! I had made several rockets by pouring this mix into sections of bamboo, coreing a hole through the center, tapeing the top off, sticking a fuse in the bottem, and ductaping it to a long stick. All this was working fine, but one thing that bothered me was that I had to take the fuses out of bottle rockets, as I didn't have the wherewithal to buy them off eBay. So to solve this dilemma, I went to the most reputable source of information I could think of, YouTube! While browsing, I found a great video by Grant Thomson found here> https://youtu.be/w-H02hwvVgI
In the video, he dissolved 60 grams of potassium nitrate and 40 grams of sugar in whateverthefuck much water. He then added twine and boiled the solution down until he was just left with damp twine. He then spread the twine out on a baking dish and put it in the oven to dry. After watching the video, my lazy ass came to the conclusion that taking the twine out of the pan, and putting it in the oven was a completely unnecessary step, and that one could just continue to heat the twine in the pan to drive off the last of the water. So I went outside, started a fire, dissolved everything in the aforementioned amount of water, added twine and began to heat it. ( keep in mind that I was using a bean can to do this because, well, I use my pots and pans for cooking food). So most of the water was boild of at this point, and everything was going according to my halfass plan. I had I ball of damp but loosely packed fuse wire, so I just continued to heat it to drive off the water. As I was doing this I had neglected to put on safety glasses because, well, only nerds wear those. As it was getting almost dry, I heard some crackling coming from the can. My first reaction was stop stiring, get my face close to the can, and look in. At that moment, my face was engulfed in a large, purple fire ball, as the hot fuse burned instantly. I fell backwards and lie on the ground for a few seconds that felt much longer than they were. When I finaly opened my eyes, I was immediately struck by the fact that, holyshit, I wasn't blind! For this I was very happy (and even more lucky)! I raced inside as fast as my newly acquired adrenalin rush could carry me, and ran for the mirror to check out my new haircut. I was not in possession of my eyebrows or eyelashes any more, but I was in possession of a newly found respect for dangerous chemicals, and that's what you should take away from this.

JJay - 30-3-2017 at 02:58

I just started oxidizing a gooey suspension of metal hydroxides to extract the chromates using calcium hypochlorite at home. This produces rather noxious fumes (which I assume are chlorine gas). I ended up putting the plastic container I was using for the oxidation in a 5-gallon bucket and putting it outside, but my entire apartment reeks of chlorine.

I haven't figured out exactly why this releases so much chlorine, but I won't be doing this reaction indoors without a fume hood again.

tsathoggua1 - 30-3-2017 at 08:39

Use of plastic keck clips during a synthesis of ICl. Even the traces making it through the vacuum grease applied round the outside of the condenser joints are pretty damn virulent, enough so that after a few hours, there are breaks right through any such clip on the side closest to the joint mating surfaces, and after a day, multiple breaks. After several days, the plastic clips were way beyond saving, having been reduced to crumbly, keck-clip shaped pieces of what used to be plastic, but now has the consistency of crumbly cheshire cheese and never mind pulling the clips off the joint, they just fell off in little pieces.

Its brutal to the dow-corning high-vac grease used as a temporary measure to reduce trace emissions still further, it turns black and plasticizes into something stiff but crumbly and brittle.

Definitely not a reagent that one would wish to breathe in. Mask filters get changed before every synthetic run, and if needs be, during the run, away from the actual process itself. About to change into a brand new set of filters even though the ones in that mask currently are not spent. Its not something that would be a good idea to rely on detecting smell, after seeing what it does to organics, and the fact it hydrolyzes rapidly on contact with water (a couple of drops from a pipette into H2O resulted in a little green puff of Cl2 and some I2 as it instantly hydrolyzed) into Cl2 and I2, I'm not risking even one whiff of the stuff.

fluorescence - 30-3-2017 at 09:55

So I read about the reaction of Titanium metal with Hydrofluoric Acid in a book. Woelen hat demonstrated pretty well how hard it is to get Titanium into solution, especially with HCl. So I tried the same thing with 40% HF in a wax-coated test tube at cold temperatures (because you have to boil it in HCl). It immediatly reacted with the Ti wire I added and so I placed the whole thing into an old plastic container I found with a transparent lid so I could film into the tube. It turned purple then it suddenly started to turn all crazy from just a small piece of Ti fumes of HF came out the test tube rose to the lid and in seconds ate through some layers of the plastic. The video will be uploaded soon to youtube but it was really crazy. I didn't expect HF to be that corrosive. It's still just a rather weak acid similar to HCl, it eats through oxides because of an interesting mechanism which increases electron density on bridging O-Atoms but for the rest of chemistry its still a regular acid. Really weird and I was lucky (wearing 3 pairs of gloves) and behind a blast shield that the stuff reacted in the box. Still just opening the lid and walking away caused my lips, so pretty much any wet part the HF could reach to become all rough for 2 days...

JJay - 30-3-2017 at 19:16

Well, considering that none of my neighbors noticed any nasty fumes last night, I guess not much chlorine was produced.

I think possibly the fumes weren't actually chlorine but were instead chlorine dioxide from dissolved carbon dioxide reacting with the calcium hypochlorite. There shouldn't have been much carbon dioxide in solution, but I can see how there might have been enough to cause noticeable quantities of irritating fumes indoors.

Oh and I did destroy a couple of plastic Keck clips with bromine fumes a while back. I have stainless ones now, but I use them infrequently.

[Edited on 31-3-2017 by JJay]

NitratedKittens - 30-3-2017 at 23:32

While boiling down a solution of pentanoic acid in dichloromethane it boiled over, onto the hotter parts of the hot plate. This was hot enough to boil the acid and form clouds of pentanoic acid vapour, and these were awful, like burning feet.

So in summary I lost lots of acid and got to experience the horror of gaseous pentanoic acid

j_sum1 - 30-3-2017 at 23:38

Butanoic acid is like last meal revisited. What does its penty cousin smell like? At high concentraion and hot, I can imagine it was not pleasant.

Sulaiman - 30-3-2017 at 23:43

Quote: Originally posted by NitratedKittens

While boiling down a solution of pentanoic acid in dichloromethane it boiled over, onto the hotter parts of the hot plate. This was hot enough to boil the acid and form clouds of pentanoic acid vapour, and these were awful, like burning feet.

just curious as to how you recognise the smell of burning feet

G-Coupled - 30-3-2017 at 23:55

Quote: Originally posted by Sulaiman

just curious as to how you recognise the smell of burning feet

Being possessed of a healthy, active imagination, I'd warrant.

[Edited on 31-3-2017 by G-Coupled]

mayko - 31-3-2017 at 11:34

>ITT: When Chemistry Goes Wrong
>40% HF

Quote: Originally posted by Sulaiman

just curious as to how you recognise the smell of burning feet

The only thing worse than recognizing the smell of burning feet.... is not recognizing the smell of burning feet.

Quote:

In another case, a young American airman was injured in a mock duel with another serviceman, when a miniature fencing foil was plunged into his right nostril, puncturing a small part of his limbic system immediately above. This resulted in a severe impairment of memory... a wide range o of perceptual and intellectual abilities was unaffected. His memory impairment was particularly noticeable with verbal material. In addition, the accident seems to have rendered him both impotent and unresponsive to pain. He once walked barefoot on the sun-heated metal deck of a cruise ship, without realizing that his feet were being badly burned until his fellow passengers complained of the uncomfortable odor of charring flesh. On his own, he was aware of neither the pain nor the smell.

- The Dragons of Eden (Carl Sagan)

NEMO-Chemistry - 1-4-2017 at 04:12

I got a new box of conical flasks from school on friday (last day of term), the often sell off things cheap this time of year. And we can buy glassware at any time at cost price

.

So opened box of flasks and grabbed one, set on work bench and poured roughly 100ml HCl (36%) into it. Pick the flask up by the neck to carry over to my temp fume hood (yes should have poured the acid in the hood), and around 3/4 of the flask just separated! I was left holding the neck and some of the sides.

They use Duran or Pyrex and being a school no Chinese rubbish. but having to clear up 100ml of HCl all over the floor with glass shards, and just a simple mask..... Not fun at all. I dumped my bag of sodium carbonate on it first.

On reviewing it all later, I still cant get over the number of noob mistakes I made! I should be well past some of them by now

.

1) new glassware, not washed first and not filled and checked for cracks etc.

2) Pouring 36% HCl away from the fume hood, just stupid and lazy.

3) Not having anything to neutralize at hand (I had to go to next room to get my carbonate), again really stupid.

4) Not having an adequate mask.........One reason I built the temp fume cupboard, so why dont I use it more!

Checked the other flasks and all have cracks in, I will get the money back, but more disappointed that I still do the really stupid and simple errors.

Like making my temp cupboard with sink in!! Then not connecting the waste of the sink up!! Lucky I discovered that while washing out a flask of acetic acid (10%).

XeonTheMGPony - 1-4-2017 at 04:59

I'm great full for the simpler mistakes, it reminds us to never be complacent.

I thermal cycle all my new glass wear as well, after a good washing I flame dry it till it is hot to the point you feel it radiating, then once cooled to room temp in the freezer it goes.

Better to break it when it isn't full of 300c H2SO4 or other nasty compounds!

NEMO-Chemistry - 1-4-2017 at 05:48

Quote: Originally posted by XeonTheMGPony

I'm great full for the simpler mistakes, it reminds us to never be complacent.

I thermal cycle all my new glass wear as well, after a good washing I flame dry it till it is hot to the point you feel it radiating, then once cooled to room temp in the freezer it goes.

Better to break it when it isn't full of 300c H2SO4 or other nasty compounds!

Silly question.....Isnt there a chance that it would break more easily on a second cycle? Like when you first use for real? Obviously that would only happen if you were boiling sulphuric acid or such!

Sounds like a good idea though, Being lazy and having a hatred of washing up dosnt help me. I am waiting for my mum to buy a new dishwasher.......... Happy day's when I bag the old one

JJay - 1-4-2017 at 05:54

This morning I was arrested for trying to steal a keg of methylamine for producing industrial quantities of MDMA for sale on the black market

Ok, actually that never happened. April Fool's!

XeonTheMGPony - 1-4-2017 at 06:04

Quote: Originally posted by NEMO-Chemistry

Silly question.....Isn't there a chance that it would break more easily on a second cycle? Like when you first use for real? Obviously that would only happen if you were boiling sulphuric acid or such!

Sounds like a good idea though, Being lazy and having a hatred of washing up dosnt help me. I am waiting for my mum to buy a new dishwasher.......... Happy day's when I bag the old one

That's the idea, if it doesn't fail during the thermal cycling it isn't going to!

You can't control if it will suddenly fail but you can chose when apx! Weak glass will not handle a full thermal cycle with out cracking or some thing but well don glass doesn't even notice it.

I rather any thing breaks while it is clean of toxic or hazardous substances on it. I am a distilaholic, I distill all my solvents as I like clean pure materials to work with, saved me allot of head aches over the years.

So a small crack when distilling acetone = burny death, and well that kind of sods up the rest of your week!

Clean glass wear is critical if you want shit to go the way you want it too, due to bad water I have to do the first wash (Soap and water) then rinse with distilled water with a bit of HCL in it to remove the carbonates from the tap water, then a final distilled water rinse!

If I need a fast turn around I rinse it with methanol that gets dumped into the wet methanol jug to be later dried for reuse, then oven dry the glass wear.

NEMO-Chemistry - 1-4-2017 at 10:03

Quote: Originally posted by JJay

This morning I was arrested for trying to steal a keg of methylamine for producing industrial quantities of MDMA for sale on the black market

Ok, actually that never happened. April Fool's!

So you did steal the keg? but you didnt get arrested for it?

.

@ Xeon

I need to get some of the lazy arse out of me! TBH if I am going to get anywhere I need to up my game, my lab is a mess and my lab book a joke

. I tell myself I dont have time, truth is I cant be arsed most the time to clean up. That is likely to bite me hard one day......

XeonTheMGPony - 1-4-2017 at 11:47

cleanliness prevents burny fireness! Lab book? Whats that? lol I was all ways terrible at paper work or keeping it.

But ya keeping things clean keeps you from getting poisoned or fires starting

tsathoggua1 - 1-4-2017 at 12:06

Why steal methylamine anyway, nitromethane isn't exactly difficult to come by, and dissolving metal reductions (acidic type rather than Birch-like) of nitromethane can reduce the nitro group to the amine. There are an awful lot of such aliphatic nitro reduction procedures around
considering both the usefulness of lower primary alkylamines, and the great utility of the Knoevanagel condensation in producing nitroalkenes from aldehydes, this kind of nitroaldol is pretty popular with the Shulgin-fanclub type chemist crowd and invariably that nitro group is going to end up reduced to the primary amine or possibly hydroxylamine.

As for cleanliness preventing burneyness..

It does usually...not always. Had a random patch of burning lawn the other day and I really don't have a clue what could have caused it.

I'm going to invest in a new set of stainless keck clips and electroplate them in something extremely resistant, such as Ir, for this kind of chemistry. Even wrapping all joints with teflon tape and greasing the clips, the only one that actually survived more than a few hours was the one near the similarly treated flask generating the Cl2. Cl2 is corrosive enough, but iodine monochloride is just plain vicious. I think some perfluorocarbon grease is called for too. The dow-corning high vac grease suffices as a temporary measure, but it gets turned to something like cement after somewhere up to 12 hours or so (I wasn't there observing so I'm not sure how long)

Interestingly enough it didn't ignite fine magnesium dust, or 30 micron Al dust. Have yet to try nickel or copper. Doesn't ignite sulfur in the solid state, haven't yet tried it on powdered sulfur. One drop on (red) phosphorus ignited the moment the two contacted, and had more ICl been dripped on to the phosphorus sample I haven't any doubt it would have been extremely violent (these tests were all done on the scale of 100s of mg or so, a few spatulas full of each test reagent when examining the oxidizing power of ICl)

The Mg was actually difficult to ignite with an external flame, but the aluminium allowed itself (again, on this microscale, I wouldn't try it with large quantities for obvious reasons) to soak in the ICl, and on applying a flame, immediately flared white hot leading behind a white glowing 'coal', that was almost certainly anhydrous AlCl3 or AlI3. (does aluminium form poly(tri)halides of the nature AlHn1/2-Hn1/2 where H=two or more different halogen atoms?)

Still not quite sure what, or how it came to happen, but the night after the oxidizing powers of the ICl were tested, some 12 hours later, in an area situated a LARGE distance from the site of the tests, which involved at most a few drops at a time of the iodine monochloride, and any residue put to the flame of a blowtorch, there was an odd, smoking liquefied hole in what used to be the dirt of what used to be the lawn. ICl hydrolyzes very quickly on contact with H2O and isn't air-stable either, and is apparently somewhat unstable towards light. On adding 1 drop to a container of water, a puff of Cl2 is instantly apparent plus the iodine content being released, more or less on contact.

So I'm actually quite puzzled by what reduced that section of lawn and soil and stones to a puddle of something black, oozing and gooey-slimy looking, giving off (suddenly, during the day, it just started up giving off smoke according to my old man and hadn't been there all day doing it)

ICl would have been the first suspect, but for the fact that so little was ever taken from the bottle, a few drops, and none of it was within maybe 6-8 meters give or take, of where this black smoking hole appeared. And the fact that any ICl would have decomposed and vaporized, dissipating into the air over a timespan of 12 hours or so.

The only other thing possible would be either PI3, which again probably wouldn't hang around a dewy morning for hours, and in any case, the RP igniting would have vaporized it completely. Sulfur halides after testing on a small (thumbnail-sized) piece of solid sulfur...again, the remains of that were cleaned up with a blowtorch and were many meters away from the site of testing. The actual synthesis of the ICl itself is contained in a closed system, with the only exit being into a suckback trap exiting into a vessel containing saturated sodium carbonate solution. And its at completely the other end of the house. Cl2 wouldn't settle like that, and it would have bleached the surrounding area, if there had theoretically been a large scale release of chlorine gas, going from accounts dating back from WWII of the gas warfare in the trenches, vegetation bleaching in the gas clouds, rather than forming a bubbling, smoking black slime, and I can't see I2 liquefying dirt and gravel, leaving a smoking crater behind.

There were other burns nearby, from phosphorus, after an alembic cracked and decided to vent WP over the lawn, but again, that isn't capable of lying dormant for a month or two or three and suddenly reigniting.

Not even sure its something I DID, given the circumstances.

[Edited on 1-4-2017 by tsathoggua1]

NEMO-Chemistry - 3-4-2017 at 03:46

nitromethane is extremely hard to get in the UK. You are allowed upto 30% if its in radio controlled model fuels. But that is very expensive to buy.

JJay - 3-4-2017 at 04:21

Seriously, though, I would be rather disturbed if my lawn spontaneously caught fire for no reason. Then again, I would probably also be disturbed if a black goo of unknown composition were seeping out of it in a puddle.

XeonTheMGPony - 3-4-2017 at 04:39

If you live in Europe very well could be a WW1 era chemical weapon IE a mustard agent that has been decomposed.

I'd be very cautious around it and alert hazmat.

NitratedKittens - 3-4-2017 at 06:34

Quote: Originally posted by j_sum1

Butanoic acid is like last meal revisited. What does its penty cousin smell like? At high concentraion and hot, I can imagine it was not pleasant.

Its not pleasant at high temps, at normal temperatures it literally smells like essence of stinky feet.

tsathoggua1 - 3-4-2017 at 13:00

I VERY much doubt that a couple of inches of lawn would spontaneously start oozing WWII leftover sulfur mustard.

The lawn didn't actually catch FIRE, it just sat there, liquefying into black, virulent looking and behaving black slime, same consistency and color of that which comes from the deliquescence of shaggy ink-cap mushrooms (Coprinus comatus), only whatever it was, caused the lawn to hiss and give off some awful smelling, acrid, choking smoke.

I am pretty sure it CAN'T have been the iodine monochloride I'd been buggering about with, since that was done 10-12 hours previously, and all remains were dealt with by means of, whilst wearing gas mask, blast shield, goggles, elbow-length gloves etc, not only confining samples to a piece of glass or stone, but once reacted, or in the case of Mg, to encourage rxn, holding a blowtorch on full blast centimeters away from the sample, and in all cases a few DROPS of ICl were employed with spatula fulls of all tested chemicals save sulfur, of which a small nugget was chipped off one of my rolls of sulfur and ICl dripped onto it from a pipette. A blowtorch was again employed by way of cleanup.

The ICl synth setup was in the garden, but again a considerable distance from the suddenly smoking, liquefied section of the dirt below the lawn. And its a closed system, under pressure of chlorine gas, enough pressure to make a loud 'whoosh' sound if the system is opened at the Cl2 generator end. Its holding its pressure for days, and under additional pressure of argon to drive the Cl2 through the columb of iodine.

Question-I've heard reference to IBr5. Does iodine form a pentachloride? if a pentabromide and higher fluorides are extant, I see no reason why ICl5 should not exist. Does it exist and if so what are its properties? I imagine it would be a most potent oxidizer if it does exist, ICl is prety snappy when it comes to burning things.

The only other thing I can think of would be the phosphorus or sulfur tests. The red P ignited instantly upon contact with ICl (a single drop caused a large and bright flare the instant it touched the phosphorus) or the sulfur test, no flames, actually very difficult to ignite that piece of sulfur, although I did eventually get it to burn, slowly and calmly after taking to it my blowlamp on its maximum gas flow rate. Again these tests were done in sequence, less than minutes between them, and this whatever the hell it was quite literally turned not just the grass, but the soil and stones below it to black, smoking ooze, and it did so relatively suddenly, hours after any fucking with a few drops of ICl. The main bottle of iodine monochloride is intact and resists it just fine, it is standing in a closed, lightless cupboard that is dedicated mainly for storage of strong acids.

And I didn't think that iodine monochloride would be a strong enough oxidizer to liquefy stone and turn it to smoking goo.

As for butyric acid, its not stinky feet. That is valeric and isovaleric acids. Butyric acid smells like refined, distilled eau de barf. Believe you me, I know. I've worked with its anhydride a fair bit (n-butyric anhydride) and even my old man, no chemist, now recognizes that stench. Propionic acid smells a bit rancid, for some reason I think 'goat-ey' when I smell propionic acid. Butyric acid smells like the result of a sexual advance from Theresa May towards any sane individual possessed of the sense of sight.

Valeric (pentanoic) and isovaleric acids are the ones that reek of cheesy feet. Butyric acid isn't pleasant at any temperature, it just smells like puke threw up, ate its own vomit and washed it down with a cup of cold sick. The anhydride doesn't smell so noxious as the acid, but of course it hydrolyzes easily and if one can detect its smell (the anhydride smells flatter, thinner, slightly vomit-like but not nearly so strongly, and it smells of a quite different shape, hard to describe. Smells a lot thicker than propionyl chloride.None of the three feel like they have any color to their respective stinks though.

Again..hard to describe...synaesthetic senses probably don't translate well at all.

tsathoggua1 - 3-4-2017 at 13:02

As for nitromethane, I've never encountered the racing fuel, looked for it but never found anywhere that sold it. But I've never found NM or nitroethane difficult to buy in the untainted form. Although I haven't actually currently GOT any NM, I do have a liter of nitroethane sitting on the lab shelves

And as for the corrosive slime pool, it wasn't of vast size, a few inches in diameter, it smoked for a few hours and then kind of died off, leaving behind a puddle of soil and stones in black, oily looking, extremely acrid stinking bubbling glorp form. I really haven't the foggiest what it could have been. I haven't buried anything in the garden, and even less have I ever buried anything that might burst open and release something capable of liquefying stone.

Thats the kind of behavior I'd expect from the likes of chlorine trifluoride, ClF5 etc. but not the iodine interhalogens, save maybe the fluorides. And I've never MADE any iodine fluorides. Only the chlorides. The bromides of iodine, and chlorides of bromine are next on my list, as well as more chromyl chloride, for an etard rxn. (the CrO2Cl2. Fun to make too) the interhalogens will see their being put to good use, although my primary motivation for synthesizing them is out of pure scientific interest.

The 'because I can' kind of reason

ICl3 is going to be next, will dissolve the leftovers from my ICl synth in pentane, or liquefied butane kept on a cryo bath, then bubble in chlorine in excess and finally evap off the alkane solvent to hopefully leave behind ICl3.

I really do want to know though if ICl5 or higher chlorides exist. AFAIK iodine goes up to a heptavalent oxidation state with fluorine, but the ionic radius of fluorine is rather small. So it might well differ for the other halogens being much bulkier in the case especially of E.g bromine. So steric effects could come into play. But chlorine? can chlorine form iodine tetra-, penta-, hexa- or heptachloride interhalogens?

[Edited on 3-4-2017 by tsathoggua1]

[Edited on 3-4-2017 by tsathoggua1]

Booze - 3-4-2017 at 16:56

I tried to make nitric acid with a very bad setup. I used ammonium nitrate (by the way I hate ammonia because of this and the smell) and I heated it up too quickly, leading it to break down and fill my garage with laughing gas. It even made my voice slightly deeper.

The Mad Plater - 9-4-2017 at 07:40

Quote: Originally posted by tsathoggua1

As for nitromethane, I've never encountered the racing fuel, looked for it but never found anywhere that sold it. But I've never found NM or nitroethane difficult to buy in the untainted form.

In Poland, only a few years ago it was possible to buy straight nitromethane in RC model shops - intended for making your own RC fuel mixes. Roughly $100 for 5L, IIRC.

Now, because of increasingly B.S. EU regulations, it's still available - but NOT to individuals (regulated as an explosive precursor).
The only viable source now is in premixed RC model fuels, up to 30% nitromethane content, roughly $40 per 5L of such mix.
The remainder is mostly methanol, some lubricating oil, and small amounts of (unknown, proprietary) combustion improvers.

EDIT: Damn it all! On top of all this, methanol is now in the same legal category as eg. HCl or conc. H₂SO₄: still available to individuals in reasonable quantities, but requires filling out a bunch of stupid PAPERWORK.
Guess how I found that out... serves me right for not reading the blasted fine print!

*****

As for my screwups - I can recount a very simple, and stupid (but fortunately harmless) one right off the bat:
During my first stainless steel electropolishing tests, a few months ago, the recipe called for conc. phosphoric acid, ethylene glycol, and water, in roughly equal proportions.
I had the acid, but not the glycol (in pure form).

Then, a "bright" idea: I have a few L of car radiator antifreeze in my shed - and that's usually roughly 50% glycol in water, with a small amount of corrosion inhibitors.
And since this was some cheap crap, it's likely to have very little of the inhibitors (none at all, even?).

So, in goes the acid, and the antifreeze, in 1:2 proportions.
A good few hours were wasted in fiddling with various values of current density, to try and get a good result.
To make a long story short - this was totally, utterly useless for any sort of electropolishing.
It did, however, make the metal surface look a bit like a very scaled down surface of the Moon, complete with deep craters, "sandy" appearance, and all that. Not the desired effect in this case, though.

Fast forward a few months - I bought some real reagent-grade ethylene glycol, and tried this again with an otherwise identical setup - and to absolutely nobody's surprise, it worked OK. (later I refined the recipe a bit, but that's another story)

So, either that antifreeze contained no glycol (something else instead to depress the freezing point?), or the corrosion inhibitors which it (should have) contained somehow "poisoned" the electropolishing process.

Moral of the story: never assume that an OTC product contains a particular ingredient, or a specific mixture of ingredients - especially if it's not stated on the label.
Especially in recent times, what with things such as acetone-free acetone, and the like.

[Edited on 10-4-2017 by The Mad Plater]

tsathoggua1 - 11-4-2017 at 12:23

Lets just say, I am thankful for the full-face shield I wear now over my goggles, after an ampoule of white phosphorus broke whilst being heat-sealed, and the WP jetted out of the neck as the amp shattered. Made quite a mess of a wooden cupboard though and filllled a room with copious P2O5 smoke and a gout of intense fire.

No harm done though thankfully, other than a bit of crisped up and shrivelled burnt hair, with the accompanying stench of seared proteins, because my hair is longer than the longest available face shields on sale I could find. Only cosmetic damage, and that, some hair singeing aside, was to a cupboard not to me.

And some damage to a small carbon crucible, when it was being used as an anode during electrolysis of a melt of caustic potash and NaOH. They fare well enough against NaOH alone, or when used as cathode, but when they are used to form the anode of an electrolytic circuit they are badly attacked by the molten caustic, especially when having to initiate melting by means of striking a pilot arc.

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