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crazyboy
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Gonna cook up some amphetamines or do you just have stuffy sinuses?
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hector2000
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i am not cooker or another thing
just i am interesting to know it
Chemistry=Chem+ is+ Try
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Picric-A
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Does anyone know what is in those little 'O2 ABSORBER' sachets you find in packs of tea leaves?
My guess would be alkaline pyrogallol but i cant be sure,
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497
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Iron powder works for that purpose but I'm not sure if that's what they are.
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Picric-A
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I thought that but upon testign with a maggnet it proves wrong.
I am going to dissolve it in water and test the PH.
edit- PH is neutral, now im clueless 
[Edited on 7-12-2008 by Picric-A]
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crazyboy
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I have been thinking about getting some good quality chemicals. I have been scrounging and making my own stuff for a while and I want some real lab
grade stuff with known purity.
So my question is who will ship to me. I don't have a company just an individual my question is what is the best company that has good prices and
ships top individuals? I have heard a lot of people here buy from big names like Fisher, Sigma Aldrich, Spectrum and Acros. But I have also heard they
only sell to big companies.
So who sells reasonably priced high quality chemicals to individuals ad hobbyists? Does anyone?
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Nicodem
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Your question is impossible to answer with a simple reply. There already is a thread about the topic and I suggest you to read trough it very
carefully since the answer is very complex and extremely geography dependent. While still doing experiments at home, I used to get chemicals trough
various sources (like friends, hardware stores, etc.), but I also bought many from chemical suppliers. I never bought directly from what you called
"big names", but always ordered from the chemical resellers. This is also the way the university labs and most research labs do in this part of
Europe. Things might be very different if you live in the USA or other parts of the world or so I heard from others, but I never heard of anybody
ordering directly from the Sigma-Aldrich-Fluka conglomerate, for example. Some minor "big names" companies like Alfa-Aesar or Abcr that do not have
official local representative offices do sell trough direct orders, but you will probably have to open an account with them which is not really worthy
if all you want to order is just a couple of things - in this case rather go trough a local reseller of chemicals (it will cost you slightly more, but
still much better that trying to deal with big companies as an individual).
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raven
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hello everybody,would liquid parrafin from a chemistshop be o.k to submerge lithium metal in.i have just got a reasonably sized sample of lithium.but
the metal is poking above the oil line leaving a fare bit exposed.
i wanted to top the oil up to the brim to completely submerge it.would liquid parafin be o.k to use as is?i think its called mineral oil in the states
,im from the u.k.
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12AX7
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Yes.
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raven
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thanks thats what i thought,but always good to get a second(3rd,4th,5th) opinion
cheers 
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Klute
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Yes, yes, and yes 
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
-Alice Parr
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Picric-A
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Dont forget you can submurge Lithium easily becuase it floats on top of practically everything.the only way you can do it is use a small bottle and
fill it with oil to the brim.
I have always boiled the oil i use to store my Lithium to 200 degrees C then leave to cool in a dessicator to make sure there is no traces of O2 or
H2O dissolved. That may be being a bit cautious though 
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Picric-A
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Just a quick question.
I plan on making some Raney Nickle for hydrogenations.
To do this you make a nickle/aluminium alloy then dissolve in NaOH to give the Raney nickle.
I know nickle has a high melting point but aluminium doesnt. Does anyone know if i melt aluminium will the nickle dissolve in the aluminium or will it
need to be hotter?
cheers
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raven
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i toped it up with liquid parafin,it worked perfectly.i was concerned that it might have contained a tinybit of water,so i tested 1st with just a tiny
bit of lithium in some parafin ,no hydrogen formed,so i figured it was all o.k...and it was.
thanks for your replys,always helpful to be reassured
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smuv
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Picric, If you need to prepare the alloy, you might be better off with an Urushibara nickel catalyst.
That being said, I am sure if you look hard enough, you must be able to find a source of a nickel aluminum alloy.
Also, for the home experimenter Pd/C is seriously worth reconsidering as it is readily available from photo supplies and requires much lower
temperature/pressures. I bought 50g of 20% Pd/C off of ebay for next to nothing, it came sealed in its original container.
P.S. If you don't get a good answer here, check out, http://www.backyardmetalcasting.com/forums/, I know you will be able to get a reasonable answer there.
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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12AX7
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Nickel and aluminum are -- what's that word? At any rate, the intermetallic formed is exothermic. It suffices to heat aluminum and nickel filings
together. When the aluminum melts, it dissolves some nickel, decides it has a taste for it and heats up, keeps on dissolving and etc. A flux would
help the aluminum make contact with the nickel, but would also evaporate (leading to gas production) when the stuff goes off...
Tim
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smuv
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Carbonyl Chloride?
If I stir a mixture of tetrachloroethylene water, and TCCA for a few hours, seperate the layers and then treat the organic phase with an alkali
solution is there ever any chance of appreciable carbonyl chloride production?
I see no obvious method for its formation, but I have seen it pop up in some very mild oxidations of tetrachloroethylene, so I want to pass it by the
forum.
Thanks.
PS Trichloroacetic acid is the desired product...
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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Nicodem
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No phosgene should form. However, tetrachloroethylene is a very electron poor alkene and will take a long time for it to react in an electrophilic
addition and under biphasic conditions (actually triphasic since TCCA is also poorly soluble in both, water and tetrachloroethylene). I suggest you to
use acetonitrile as cosolvent (85% acetonitrile/water should do) and leave it running for several days (do not use acetone as HCl forms during the
reaction and will catalyse the alpha-chlorination of acetone). A homogeneous reaction will also prevent side reactions (like for example the addition
of Cl2 forming hexachloroethane due to absence of H2O in the organic layer rather than forming trichloroacetic acid). Do you have any related
literature examples on halohydration of tetrachloroethylene? It appears to me that electrophilic reactions on tetrachloroethylene are not particularly
rapid.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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gnitseretni
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Some folks make their own fuses with black powder. I don't have black powder, but I do have sodium nitrite, hexamine and sulfur. Could I use my sodium
nitrite as a substitute for the potassium nitrate and hexamine for the charcoal and is there a way to calculate how much I need to use of which?
Any help would be appreciated.
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not_important
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Sodium nitrite is not as good of oxidiser as the nitrate, and with both of those the sodium salts are
somewhat hygroscopic and so tend to get damp if exposed to the atmosphere.
Charcoal is so easy to get I'd try just a bit to get or make some and use it. Rather pure charcoal can be had by baking plain sugar, there's even a
preparation in Inorganic Synthesis volume 2.
[Edited on 11-12-2008 by not_important]
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hissingnoise
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IIRC, NaNO3 is very hygroscopic (not sure about the nitrite); hexamine is a weak base *and* hygroscopic.
I'd say the mix would be very unpredictable, at best.
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gnitseretni
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if I were to leave the sodium nitrite in the open, how long would it take for it to turn into the nitrate? Hours, days, weeks? And is there a test I
could to tell the two apart from each other?
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Panache
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Filter Paper dryness
I just thought about my collection of whatman filter papers this morning and wondered if they are at all hydroscopic and/or gas adsorptive and if so
does that mean for sensitive to water/O2/CO2 work should the papers be kept in a vacuum dessicator, that would be sooooo convienent.
thanking people in advance
mark
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smuv
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@Nicodem, I have searched and I do not. I suspect though the halohydrin is unstable and readily rearranges to the epoxide/carboxylic acid. I agree
though, tetrachloroethylene should be an unreactive substrate, but I still think it is worth a smallscale shot.
Is TCCA so insoluble in tetrachloroethylene? I recall seeing TCCA reactions done in DCM (albiet more polar than tetrachloroethylene) without
co-solvent, so I thought the solubility in tetrachloroethylene wouldn't be SO bad.
The best method to do this, would be to pass oxygen through tetrachloroethylene for a few days at elevated temperatures, and I might end up doing that
if I fail with the TCCA method.
Of interest, the product of the rearangement of the epoxide in anhydrous conditions is trichloroacetyl chloride.
For more info about the reaction with oxygen see US2321823, and 'Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 11, pp. 1849-1852.' linked
below.
PS whether or not it is prudent, halohydrin formation in aqueous acetone is known to litterature...that being said, on a preparative scale I would be
nervous to try it.
[LATE EDIT] Ok you were right TCCA seems to be pretty insoluble in
tetrachloroethylene...I am still giving it a try w/o cosolvent because I don't have acetonitrile on hand (I should really order some).
[Edited on 12-12-2008 by smuv]
Attachment: oxidation_bromovinyl_compounds_molecular_oxygen.pdf (119kB)
This file has been downloaded 899 times
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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octave
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I'm helping out a friend come up with a project that involves chemistry and basic calculus or trigonometry(He wants sin, cos, or tan in an equation
that is used in chemistry), but have come up with nothing. Could anyone help me out?
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