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Author: Subject: When Chemistry Goes Wrong
j_sum1
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[*] posted on 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.




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JJay
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[*] posted on 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]
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The Volatile Chemist
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[*] posted on 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]




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[*] posted on 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!
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[*] posted on 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.
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[*] posted on 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 !
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[*] posted on 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...
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[*] posted on 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 . . . ?

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[*] posted on 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.

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[*] posted on 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 )
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[*] posted on 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!
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[*] posted on 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..
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[*] posted on 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]




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[*] posted on 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!)
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[*] posted on 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 :/



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[*] posted on 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.



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[*] posted on 23-2-2016 at 05:01


Quote: Originally posted by blogfast25  
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]


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 :P

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?
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[*] posted on 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.




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[*] posted on 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.




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[*] posted on 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]




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[*] posted on 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.



shelf support.jpg - 54kB




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[*] posted on 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.
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[*] posted on 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.

IMG_1849.JPG - 54kB


update:

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





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[*] posted on 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! :)
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[*] posted on 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>
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