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tetrahedron
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it sure looks like it. or a hard grain lodged itself between the joints and caused an invisible circular scratch upon turning.
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kuro96inlaila
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Quote: Originally posted by White Yeti  | It might be sabotage... Do you share your glassware with other people?
You can only make such a clean cut with a glass cutter. With time, heating and cooling the glass would eventually break. |
No,it is just me who use it .The fact that it look like glass cutter cut that
baffled me.
| Quote: Originally posted by tetrahedron |
it sure looks like it. or a hard grain lodged itself between the joints and caused an invisible circular scratch upon turning. |
Hard grain is the plausible cause of this accident.
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Eddygp
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A hot test tube dropped in a cold water bath... CRACK! thought it was Pyrex.
there may be bugs in gfind
[ˌɛdidʒiˈpiː] IPA pronunciation for my Username |
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Hexavalent
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Nitric acid fumes burning my nose....lovely.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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kuro96inlaila
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Today I decided to purify the red phosphorus which I obtained a couple days ago.It is from an old source so the quality isn't good.It appear to be
hygroscopic powder which the real red phosphorus isn't.
I follow the purification method described on sixth edition of "Purification of Laboratory chemicals":
| Quote: |
Phosphorus (red) [7723-14-0] M 31.0, m 590o/43atm, ignites at 200o, d 4 20 2.34.
Heat it for 15minutes in boiling distilled H2O, allow it to settle and wash it several times with boiling H2O.
Transfer it to a Büchner funnel, wash it with hot H2O until the washings are neutral, then dry it at 100o and store it in a desiccator.
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So I started to boil it in distilled H2O in a beaker using heating mantle.It heat up and boil steadily until one point it bumped out of the beaker
onto the heating mantle's fiberglass wool.I quickly turn off the heating mantle and took the beaker out of the heating mantle.Some of the red
phosphorus slurry had dried on he fiberglass wool.
After it cools down I scraped off the red P and vacuum cleaned it.It didn't clean it all the way but pretty much of the red P were sucked off.I
decided to give the HM a test run.So after the HM reached auto ignition point of red P,the stained fiberglass started to smoke and glows.After a half
a minute it stoped and I stopped the test run.
Stain left after the test run.
Anyway the other red P have been successfully purified.The stain on the HM worries me,does it give side effect on their performance?
[Edited on 12-2-2013 by kuro96inlaila]
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woelen
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I would take this heating mantle outside and allow it to heat at maximum heat for an hour or so. In this way I expect most of the red P to disappear
and the formation of smoke to stop after a while. If it does not give off any smoke anymore and still heats OK, then you can safely assume that it is
not really harmed.
The reason why I say you to do this outside is that if you get fire or a short circuit then at least you don't have the mess in your house. Assure
that you can quickly disconnect the heating mantle from the power supply and have a bucket of water nearby (in case of emergency FIRST!!! disconnect
from power supply, then use water to kill any fire or overheating).
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kuro96inlaila
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Thanks for the advices woelen,
I'll try it tomorrow.
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Pyro
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I broke a 600ml beaker drying CaCl2 in the microwave
all above information is intellectual property of Pyro. |
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Hexavalent
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I dropped my nice 100 mL porcelain evaporating basin whilst washing it...so I wrapped it in a towel, took a hammer to it and made boiling chips from
it
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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kuro96inlaila
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@Pyro and Hexavalent:Things do happen aren't they?
Ok,I have give the HM another test run as woelen described.After a moment it start to smokin' but it is only a faint smoke.A few minutes later it
stopped smokin'.Then everything looks fine to me.
But after I stopped the test run,I realised that the stained fiberglass matting had became brittle and crumble when I poked it.
I vacuum cleaned the spot because I thought it is bad to have fiberglass particles lying around.
Here's how it look like after the cleaning:
Does this alter the HM's performance?
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Magpie
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If you could find some fiberglass fabric at a hardware store or auto parts store you could probably sew a patch over the bare area.
The bare spot might be a hot spot but my guess is that it would work ok as is.
The single most important condition for a successful synthesis is good mixing - Nicodem
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repo1030
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When I was a kid and first starting out in chemistry I did the HCl and Zinc experiment. I made the mistake of picking the test tube up with no gloves
on after the reaction stopped. Boy! Was that test tube HOT! Needless to say I dropped the test tube causing it to smash on the floor.
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Endimion17
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| Quote: Originally posted by kuro96inlaila |
Today I decided to purify the red phosphorus which I obtained a couple days ago.It is from an old source so the quality isn't good.It appear to be
hygroscopic powder which the real red phosphorus isn't. |
Actually, it is hygroscopic. Not the RP itself, but its products of reaction with air. RP reacts with oxygen and moisture very, very slowly, but the
product, phosphoric acid, is so hygroscopic it makes it all clumpy in few years. It seems the deterioration is exponential if the powder is exposed to
the atmosphere, as if some catalysis is in order. I honestly don't know.
If you let it in sit for decades (30+ years) in a not so well closed bottle it will get wet. The top will be diluted acid, and the bottom will be like
a fine, wet, red sand.
The closest thing I can describe it with is the red sludge from Ajka in Hungary.
[Edited on 25-2-2013 by Endimion17]
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kuro96inlaila
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| Quote: Originally posted by Endimion17 | | Quote: Originally posted by kuro96inlaila |
Today I decided to purify the red phosphorus which I obtained a couple days ago.It is from an old source so the quality isn't good.It appear to be
hygroscopic powder which the real red phosphorus isn't. |
Actually, it is hygroscopic. Not the RP itself, but its products of reaction with air. RP reacts with oxygen and moisture very, very slowly, but the
product, phosphoric acid, is so hygroscopic it makes it all clumpy in few years. It seems the deterioration is exponential if the powder is exposed to
the atmosphere, as if some catalysis is in order. I honestly don't know.
If you let it in sit for decades (30+ years) in a not so well closed bottle it will get wet. The top will be diluted acid, and the bottom will be like
a fine, wet, red sand.
The closest think I can describe it with is the red sludge from Ajka in Hungary.
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Thanks,Endimion17!
I learnt something new today.
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elementcollector1
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Just lost a loyal beaker to the war effort.
It will be missed.
...And replaced.
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
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Mailinmypocket
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I noticed the secondary container which hold my bottle of anhydrous aluminum chloride was a bit frosty looking. I decided to Wrap the threads in
Teflon tape and whatnot, and had a little stupid idea... To smell the air inside the secondary container. Don't ask why. Anyhow- needless to say I
almost screamed from the HCl gas present in there!!!
Oh aluminum chloride- so tame
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DrSchnufflez
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My 400mm Liebig condenser shattered whilst I was washing it
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zenosx
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Ouch, that's an expensive bad day....
My only irritation this last month is my stopper from amazon was 14/20 instead of 19/22
A question that sometimes drives me hazy: am I or are the others crazy?
Albert Einstein
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zenosx
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| Quote: Originally posted by Magpie | If you could find some fiberglass fabric at a hardware store or auto parts store you could probably sew a patch over the bare area.
The bare spot might be a hot spot but my guess is that it would work ok as is. |
I would go this route as well. If you can try to keep the thickness near to the original it shouldn't cause a hot/cold spot.
A question that sometimes drives me hazy: am I or are the others crazy?
Albert Einstein
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madscientist
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| Quote: Originally posted by UnintentionalChaos | | Don't ever shake a flask with a stirbar in it...I had a rather large stirbar in a 1L, 4-neck RBF and one good shake while cleaning put it cleanly
through the side wall. I almost cried. That was my fanciest flask and one of only 2 1Ls that I owned. I picked up a 3-neck 1L on ebay though, to
replace it, so all is okay...just cost me $30. |
Now, for those of you with rotovaps, think about what would follow if this happened while pulling off solvent. Don't ever leave stirbars in flasks
that are anything but stationary!
I weep at the sight of flaming acetic anhydride.
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Mailinmypocket
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Gross Alert...
While reaching to grab something next to an extremely hot hotplate, my finger hit the HOTplate. Skin stuck to it I'm lucky my nail didnt die... This is almost a week later!!
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Pyro
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WTF? how did it get so damaged? I once put my hand on a red hot piece of steel and just had a big blister! looks very painful!
all above information is intellectual property of Pyro. |
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Mailinmypocket
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| Quote: Originally posted by Pyro | | WTF? how did it get so damaged? I once put my hand on a red hot piece of steel and just had a big blister! looks very painful! |
If only I knew... I've had bad burns before but this time when I pulled away the skin just... Came off.. Very nasty indeed, and painful, especially
when you go to reach in your jeans pocket and forget about it!! It'll be fine though- they don't call them hot plates for nothing apparently. Maybe
it has something to do with the ceramic top...
[Edited on 29-3-2013 by Mailinmypocket]
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Hexavalent
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My hotplate has a coil underneath it that expands when the hotplate heats up, allowing a small brass metal tab with "HOT" written on it in red
lettering to protrude out. This gives a clear indication of whether or not the hotplate is hot, and indeed how hot it is, i.e. by how far out
the tab is extended.
Suffice is to say that this feature has probably saved me from some very nasty burns in my time.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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Mailinmypocket
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| Quote: Originally posted by Hexavalent | My hotplate has a coil underneath it that expands when the hotplate heats up, allowing a small brass metal tab with "HOT" written on it in red
lettering to protrude out. This gives a clear indication of whether or not the hotplate is hot, and indeed how hot it is, i.e. by how far out
the tab is extended.
Suffice is to say that this feature has probably saved me from some very nasty burns in my time. |
Same here... Mine has a flashing triangle light thing that says "Hot Top" when the unit is above 60c, except stupid me knew damn well it was hot, ah
well... Live and learn I suppose otherwise that light has also saved me a few
burns I'm sure.
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