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Author: Subject: Bad days in the lab or with glassware?
JJay
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[*] posted on 17-7-2018 at 10:05


My three year old pricechopper2011 kit... let's see here... The Claisen adapter broke under a stir bearing, the Vigreux got smashed, the 250 mL flask has been replaced 3x, the sep funnel got dropped, the thermometer met a tragic end when it was sucked into a flask at high velocity under vacuum, and the Liebig was chipped by high leverage with a steel rod while cleaning. Aside from the Claisen adapter, everything broke due to accidents or abuse. I don't think I'd fare much better with American glass, but I will say that I've never broken anything I've gotten from Dr. Bob (other than the 14/10 high-temperature phenolic caps I melted).

I really don't think I break more glass than average. I clean and reuse all of my jointware, but in my view, it's basically all disposable.

[Edited on 17-7-2018 by JJay]




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Sulaiman
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[*] posted on 14-8-2018 at 09:05
Follow up on broken Claisen adapter


I ordered a new 24/29 Claisen adapter to replace my broken one, cheap Chinese as usual.
Surprisingly there were no visible bubbles in the glass,
but the glass was badly scratched so I asked for a replacement.
Today the replacement arrived - no scratches but bubbles instead :P

I tried to remove the broken part of my old Claisen and discovered how brittle the glass was around the joint.
I guess it was not annealed.
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Heptylene
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[*] posted on 14-8-2018 at 11:41


Goddammit! I broke by 250 ml pressure-equalizing addition funnel yesterday, in the most stupid way possible.

I was trying to purge with argon an apparatus previously under vacuum by connecting said apparatus directly to an argon cylinder. I let the gas flow in and of course the pressure got too high inside the apparatus. My addition funnel jumped from the 3 neck RBF it was connected to and fell on the groud, breaking the bottom ground glass joint in the process. I'll have to replace it soon because it is a very hand piece of equipment, that some reaction absolutely require. The two things that bug me the most with this are:
1. I KNEW this would happen but I thought I could get away with using that argon cylinder directly. Should have used a balloon to transfer the gas instead.
2. I had only used that addition funnel twice!

This happened while preparing a dry apparatus for a somewhat large scale grignard reaction (0.2 mole PhMgBr). On the upside, the reaction went extremely well even without the addition funnel. The magnesium reacted immediately with the bromobenzene, and nothing blew up or boiled over.

I also broke a 250 ml flask recently while trying to scrape a solid from inside of it. This ALWAYS happens when scraping solids from glass containers, everything else I have ever broken was when scraping something from somewhere, but I always think I can get away with it.
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fusso
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[*] posted on 18-8-2018 at 06:37
Spilt oxalic acid


Loss is ~10g even after collecting most solids that didnt touch the table:mad:

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elementcollector1
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[*] posted on 18-8-2018 at 09:03


Recrystallize it, maybe? If you haven't already thrown it away, that is.



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JJay
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[*] posted on 18-8-2018 at 14:23


I crushed my pricechopper2011 Liebig in a clamp. :(

It's actually still usable if I wrap some tape around it, but I think it is time for it to retire. I really need to stop clamping things so tightly....




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fusso
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[*] posted on 24-8-2018 at 09:17


Quote: Originally posted by elementcollector1  
Recrystallize it, maybe? If you haven't already thrown it away, that is.
Oxalic acid is pretty cheap so I won't bother a recrys. So I just threw it away.



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weilawei
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[*] posted on 11-9-2018 at 10:19


I'm down one 50mL beaker and I cracked the thermometer joint on my short path head. I don't usually have an issue with stuck joints, but I went with Teflon sleeves for the last project. Not my favorite, and they always cause trouble, but I don't know many great substitutes.
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weilawei
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[*] posted on 16-10-2018 at 19:02


Broke a 1L 24/40 Erlenmeyer flask tonight. Clean, but annoying. Does anyone else feel like they break more glassware the more time they spend in the lab (i.e., rate of breakage increases)? I have been spending all my non-work waking hours at the bench. Maybe that's just a cognitive bias from being more constantly exposed to it?

It sure doesn't make my wallet feel any heavier.

EDIT: I see I was the last person to post in this thread also. Doh. Man, that last post felt like last week. Where did the month go?

[Edited on 17-10-2018 by weilawei]
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Elrik
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[*] posted on 16-10-2018 at 21:12


My last losses were a 250 ml beaker that jumped off a ring stand that got stuck to the bench somehow [admittedly sloppy technique] and last month my mother went in my kitchen and broke my only 500 ml volumetric flask. Both pieces were bought by my grandfather right after he defeated hitler and entered college. Bad several weeks for 73 year old glass.

Quote: Originally posted by JJay  
...the thermometer met a tragic end when it was sucked into a flask at high velocity under vacuum...

Is there any trick used to prevent that? Like electrical tape on the thermometer just above the adapter. Or is such an incident just very rare?
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Sulaiman
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[*] posted on 17-10-2018 at 05:16


Quote: Originally posted by Elrik  

Quote: Originally posted by JJay  
...the thermometer met a tragic end when it was sucked into a flask at high velocity under vacuum...

Is there any trick used to prevent that? Like electrical tape on the thermometer just above the adapter. Or is such an incident just very rare?


Under full vacuum the force on an 8mm diameter thermometer is about 500g,
many thermometers have smaller diameters.
So carefully pull/push the thermometer in its seal/adapter with about +/- 1 kg force to test.
At higher temperatures I do not know if the thermometer will be gripped more or less securely.

I have thermometer pockets for thermocouples, and two jointed thermometers,
partly due to my fear of vacuum-propelled thermometer accidents.

P.S. My cheap-Chinese '500ml distillation kit' came with a thermometer still head adapter,
- and a thermometer that was too thin to be gripped well.
The adapter works fine with my thicker thermometers or glass tubing
- at atmospheric pressure.


I consider it unwise to use the O-ring type thermometer adapters with vacuum.

[Edited on 17-10-2018 by Sulaiman]
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FloridaAlchemist
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[*] posted on 17-10-2018 at 08:21
Thermometer Clamp


When doing vacuum distillations I use these type of clamps to hold the thermometer in place.

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DavidJR
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[*] posted on 17-10-2018 at 14:30


Quote: Originally posted by Sulaiman  

I consider it unwise to use the O-ring type thermometer adapters with vacuum.


Honestly even though I have a handful of the o-ring type adapters, I seldom ever use them. I don't like how the thermometer can wobble about.

The glass thermometer wells are just much better. You can put a mercury or spirit thermometer inside, or, as I prefer, a thermocouple probe.
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weilawei
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[*] posted on 22-10-2018 at 10:59


I usually replace the o-ring with a good wrapping of teflon--enough to really get it jammed in the thermometer adapter (which is the two-piece kind that screws around the thermometer and clamps down on it). Never had it move, though sometimes adjusting it requires taking it back out, cutting the tape, retaping it, etc..

I did, however, shoot the safety release stopper out of my setup the other night. Put a dent in the ceiling and broke the stopper in half, but no other damage or mess. Really reinforces how important good lab practice is when stuff goes sideways.

[Edited on 22-10-2018 by weilawei]
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esquizete_electrolysis
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[*] posted on 26-10-2018 at 10:53


I once was trying to make an electric stirrer and was trying to activate the magnet while the motor was going, and I was using one AC current and A DC current. Long story short, the circuits crossed and killed my power supply.
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[*] posted on 26-10-2018 at 11:51


I was recrystallizing some benzamide (about 15g) from toluene and I accidentally knocked over the beaker. Now my 7$ hotplate is covered in a healthy layer of benzamide :(. Fortunately, my hotplate stirrer should arrive and if this sort of accident happens again it should be pretty easy to clean the ceramic surface (my current hotplate has some sort of black semi-sticky surface and I'm not able to remove the benzamide at all)
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Herr Haber
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[*] posted on 7-11-2018 at 04:19


This morning I took a 2L flat bottom flask in the shower to get rid of the big Potassium sulphate cake that had settled in the bottom.

Gave a few swirls, cake separated from the bottom, turned the flask to empty the water and... crash !
The weight of the sulphate salt broke the flask.
Better now than during a distillation !
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hissingnoise
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[*] posted on 7-11-2018 at 04:36


My deepest condolences.

Next time distilling HNO3, I'll be using the sodium salt just to see how much easier the NaHSO4 cake is gotten rid of...

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Herr Haber
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[*] posted on 7-11-2018 at 12:17


Quote: Originally posted by hissingnoise  
My deepest condolences.

Next time distilling HNO3, I'll be using the sodium salt just to see how much easier the NaHSO4 cake is gotten rid of...



I can answer that. I did three runs this weekend.
2 with sodium nitrate and the last one with potassium nitrate as I didnt have anymore dried sodium nitrate ready.

With sodium it took less than an hour using hot water and a few water changes. Cold water works fine, you just have to change it a few times more.
Cold water and potassium salt is well... 10 on the scale of pain.
Not much better with hot water but at least it's doing "something".

It will now become standard SOP to fill the flask with water as usual when I'm done but instead put it back on the heating element.

At least I finished dissolving the silverware that was sitting in my 3L reactor.
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[*] posted on 8-11-2018 at 05:33


Quote: Originally posted by Herr Haber  
Quote: Originally posted by hissingnoise  
My deepest condolences.

Next time distilling HNO3, I'll be using the sodium salt just to see how much easier the NaHSO4 cake is gotten rid of...



I can answer that. I did three runs this weekend.
2 with sodium nitrate and the last one with potassium nitrate as I didnt have anymore dried sodium nitrate ready.

With sodium it took less than an hour using hot water and a few water changes. Cold water works fine, you just have to change it a few times more.
Cold water and potassium salt is well... 10 on the scale of pain.
Not much better with hot water but at least it's doing "something".

It will now become standard SOP to fill the flask with water as usual when I'm done but instead put it back on the heating element.

At least I finished dissolving the silverware that was sitting in my 3L reactor.


I simply put it in the microwave for 10 second bursts. The cake easily breaks apart with a little hot water. Done cleaning in 5 minutes instead of 50.
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Herr Haber
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[*] posted on 9-11-2018 at 04:20


This is not a good week for glassware.
Yesterday I received a small order from Deschem.
I unpacked everything and put it in the "to be cleaned" plastic bin.

Except for that little thermometer well that stayed hidden on the blanket until I went to bed and sent it around flying around the room... Bits of glass everywhere at the foot of my bed. I'm glad I didnt wake up tonight !
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[*] posted on 14-12-2018 at 18:50


I recently had an hydrochloric acid vapor incident in where I had generated so much without knowing it (I thought it had been consumed and it ate through a metal bit in my fume hood and forced my to leave for an hour hour two to let the room air out. That was fun.



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[*] posted on 17-1-2019 at 09:41


Here's a fun thread about laboratory mishaps and unsettling discoveries (multiple picric acid evacuations, containers labeled only "Open this and you'll be sorry", body parts, etc)

https://twitter.com/DrMRFrancis/status/1085691863200419840




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Abromination
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[*] posted on 25-1-2019 at 15:54


Once again, another bad lab day. It was above freezing with a nice breeze outside so I decided to make today a lab day. I decided to make some sulfuric acid via the SO2 and oxidizer method. I had finished my first dropwise addition of hydrochloric acid to the sodium metabisulfite and had decided to add a bit more. I added more acid to the addition funnel and attempted to dropwise add it, although it became stuck open and all of the acid poured in at once. Instead of getting away from my gas generator, I made the second mistake of closing the stopcock. In case of a pressure build up when assembling the glassware, I had used a vacuum distillation sidearm with a stopper and a tube leading to my oxidiser which would pop out if it got to high. Here comes the third mistake: I was standing infront of the stopper. It shot out and hit me in the chest and sprayed a cloud of sulfur dioxide vapor right at me. I got a lung full of it before I got a way but was otherwise fine.
Let my ignorance and stupidity be a lesson to others.




List of materials made by ScienceMadness.org users:
https://docs.google.com/spreadsheets/d/1nmJ8uq-h4IkXPxD5svnT...
--------------------------------
Elements Collected: H, Li, B, C, N, O, Mg, Al, Si, P, S, Fe, Ni, Cu, Zn, Ag, I, Au, Pb, Bi, Am
Last Acquired: B
Next: Na
--------------
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Mood: :) Happy about new glassware :)

[*] posted on 25-1-2019 at 16:03


Cracked my beaker while cleaning off burnt nitrates and pushing to hard while scraping. one of my Erlenmeyer flasks cracked internally from heat shock. Like the cracking is inside the glass and doesnt actually go through the walls.
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