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12AX7
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Quote: Originally posted by Sedit ![](images/xpblue/lastpost.gif) |
I have a question. I got a paint thinner that contains acetone,DCM,MeOH,Toluene and KOH.
I can not seem to seperate the layers very well using water and distillation bumps so bad even with boiling chips. Any suggestions on whats going on
here. Im shocked DCM and KOH can even be in the same solution since my instincts tell me it would be a bad idea but I guess it can.
I only want the toluene and DCM so perhaps steaming it would be my best option I guess. Right now its my cheepest over the counter source of Toluene.
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Well geez, that sounds like an awful mix... like it could peel the paint right off your walls!....oh... ![:P](./images/smilies/tongue.gif)
Hmm, acetone shouldn't be stable with KOH. It should undergo aldol condensation to mixed products (= black tar).
The acetone (if that's what it is) and MeOH are probably keeping everything miscible. I wonder if a sufficient quantity of H2O would break it into a
"salted out" KOH+H2O layer, also containing most of the MeOH and acetone, with a DCM+toluene layer adjecent (above or below, depending on the ratio of
the two, and how "salty" the water gets). If the densities are too similar, they won't seperate very well, and surfactants will prevent coalescence.
I offer no guarantees...
Other than that, KOH could at least be neutralized with, say, H2SO4, precipitating insoluble K2SO4, without adding much water to the mix (HCl would
work, forming KCl, but commercial HCl acid comes with a lot of water). You could then try distilling it again: maybe removing the salt will prevent
it from bumping so much.
MeOH could be absorbed in CaCl2. This also works for H2O and EtOH. I don't know about acetone. If there's a lot of water present already that you
didn't mention, this might not be as practical.
Tim
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solo
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Quote: Originally posted by solo ![](images/xpblue/lastpost.gif) | I have Nickel acetate and need Nickel chloride....is there a way to convert it to the chloride salt ....have looked in google and found
nothing....will most likely be found in some inorganic text...will keep looking, but if someone knows i would appreciate the assist.....solo
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.....not sure how to convert nickel acetate to the desired chloride, any more suggestions.....solo
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not_important
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Do you actually need the chloride? If so, ppt the basic carbonate, wash well, dissolve in HCL. A wasteful but simple way is repeated evaporation
with hydrochloric acid. Do it in a distilling rig without taking to the point of crystal formation, capture the AcOH-HCl-H2O mix that comes over; NiCl
in hydrochloric acid in the still pot.
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solo
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.......thanks , need it as a catalyst for an oxidation reaction .......nickel acetate won't work.....solo
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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mewrox99
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I have a quick question about pH, pOH and H3O+ concentration. Am I doing this right
Say I have a solution of HCl with an H3O+ concentration of 0.1mol-L
To work out it's OH- concentration I would do -log[0.1] to get a pH of 1
And go 14-1 to get a pOH of 13. OH- = 1.00*10^-pOH
So my OH- concentration is 1.00*10^-13
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Random
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Can I reduce ketones, carboxylic acids or aldehydes with iodine (HI) and red phosphorus?
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12AX7
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Specifically, it's not 14, but the pKa of water, which is 14.something.
If you don't mind being off by a fractional amount, then 14 is close enough. Just don't write the result as 1.00 x 10^-13, because that is not the
number's accuracy.
Tim
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not_important
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Yes, no, yes. How far do you want to reduce them? HI can take C=O to CH2, plenty of other reducing methods will take C=O to HCOH
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Nicodem
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If they are not enolizable.
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DJF90
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Quote: Originally posted by 12AX7 ![](images/xpblue/lastpost.gif) | Specifically, it's not 14, but the pKa of water, which is 14.something.
If you don't mind being off by a fractional amount, then 14 is close enough. Just don't write the result as 1.00 x 10^-13, because that is not the
number's accuracy.
Tim |
I thought the pKa of water was 15.7...?
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Sedit
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Quote: Originally posted by 12AX7 ![](images/xpblue/lastpost.gif) | Quote: Originally posted by Sedit ![](images/xpblue/lastpost.gif) |
I have a question. I got a paint thinner that contains acetone,DCM,MeOH,Toluene and KOH.
I can not seem to seperate the layers very well using water and distillation bumps so bad even with boiling chips. Any suggestions on whats going on
here. Im shocked DCM and KOH can even be in the same solution since my instincts tell me it would be a bad idea but I guess it can.
I only want the toluene and DCM so perhaps steaming it would be my best option I guess. Right now its my cheepest over the counter source of Toluene.
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Well geez, that sounds like an awful mix... like it could peel the paint right off your walls!....oh... ![:P](./images/smilies/tongue.gif)
Hmm, acetone shouldn't be stable with KOH. It should undergo aldol condensation to mixed products (= black tar).
The acetone (if that's what it is) and MeOH are probably keeping everything miscible. I wonder if a sufficient quantity of H2O would break it into a
"salted out" KOH+H2O layer, also containing most of the MeOH and acetone, with a DCM+toluene layer adjecent (above or below, depending on the ratio of
the two, and how "salty" the water gets). If the densities are too similar, they won't seperate very well, and surfactants will prevent coalescence.
I offer no guarantees...
Other than that, KOH could at least be neutralized with, say, H2SO4, precipitating insoluble K2SO4, without adding much water to the mix (HCl would
work, forming KCl, but commercial HCl acid comes with a lot of water). You could then try distilling it again: maybe removing the salt will prevent
it from bumping so much.
MeOH could be absorbed in CaCl2. This also works for H2O and EtOH. I don't know about acetone. If there's a lot of water present already that you
didn't mention, this might not be as practical.
Tim |
I did a simple distillation of the mixture and the ratio of componates are in order, MeOH, Acetone, DCM, Toluene, KOH. So there is little KOH in the
mix and it does not appear to be affecting verymuch at all. I did get some interesting results as for the first time ever after adding water(to make
it fluid and distill better) and distilling I got a quadphasic mixture*(is that even a word)
Question: what sort of azeotrops am I looking at here and is toluene and DCM able to mix with each other?
Im pretty sure I have managed to seperate them pretty well but I was shocked to smell the remains of the flask one time and smell what I am almost
positive was the smell of benzaldahyde.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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Magic Muzzlet
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I have a question about a result of methoxylation of bromovanillin. After a day of boredom I decided on a whim to try out the reaction again after
having many failures in the past. The procedure is much like the ullmanisation that has been posted on this board, and on rhodium etc. using sodium
methoxide, methanol, DMF and CuCl. I was reading hyperlab and saw attempts, and having nothing better to do I gave it one more shot. Methanol was
anhydrous as well as DMF, CuCl was fresh, bromovanillin was made by me and was nearly a white powder. However I used sodium methoxide from spectrum
which had hardened. This is what I did:
To a 250ml rbf with stirbar and condenser was added 7g sodium methoxide powder (large excess due to unknown purity, not all of it dissolved) followed
by 33ml of MeOH. Next a solution of 7g bromovanillin and 700mg of CuCl in 20ml DMF was added. Unlike other attempts I observed no blue/greenish
coloration, it stayed beige. It did grow thick with the phenolate however. The mixture was refluxed for 45 minutes with stirring in a boiling
waterbath. Next the setup was switched to distillation and over 1hr 30mins methanol was distilled out. At the end it was a much darker red. Solution
cooled, added ~100ml water and filtered some bromovanillin and what I assume was copper. Next I acidified the filtrate with HCl, and it turned purple,
glittering leaflets started to precipitate. I filtered these, washed with 300ml dH2O and saved them. I still have the remaining filtrate but stopped
there for the night. After drying I took a crude melting point with oilbath, test tube and thermometer. They melted at right around 115ºC. I tried to
form an adduct with about 200mg of the crystals in a test tube, 2ml of warm methanol and 2 ml of warm sat. metabisulfite solution. Few hours later it
seemed to have formed but I have not processed it further.
My question is are these crystals, which weigh 6g, syringaldehyde? I have never had a pure sample before, they have a very low odor I can best
describe as woody/sweet but this smell is veryyyyy faint. I made a solution of 200mg in few ml of methanol, added 1ml of ~10% NaOH and it turned
yellow, and then oxidized to dark brown upon exposure to air. I realize in preps the solution is usually acidified then filtered, then the filtrate
extracted with ethyl acetate or DCM, but I have never read about purple coloration and these crystals are completely insoluble in water and the
melting point is close to that of syringaldehyde. Thanks for any help.
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Panache
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At what point is is more efficient to compress air and release it than to 'pump' it with a fan of some sort. The run i have is a 30m, 3inch steel pipe
that was once used for fire service (ie water, high pressure). I want to use it to move air from one end of the factory to the other and its just
sitting there already mounted.
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solo
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I read someplace that the AlHg reductive amination causes recimization.....of course working to the desired amine via the golden ketone the product
will always* be recemic......so no one cares or is concerned, however it's an important point i would like to hear some explanation on how that
occurs....there is a pearl at the end of that tunnel......solo
*there are some exceptions , if using a single enantiopure to aminate would be one of them, but maybe not it may just rotate it to the opposite
enantiomere, that would indeed be interesting
[Edited on 1-12-2010 by solo]
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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Random
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Can I make manganese (ii) acetate from acetic acid and mno2 or do those compounds even react?
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ScienceSquirrel
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The simple answer is no if you are using most grades of manganese dioxide as it is pretty inert.
I would suggest using manganese carbonate, either freshly prepared or purchased, it is quite readily avilalable and a decent grade of acetic acid.
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Arthur Dent
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No you can't make Mn acetate that way, but if you're using the gunk from carbon batteries, some diluted acetic acid will help dissolve and separate
some of the zinc impurities, making your MnO2 a bit cleaner. Make sure to wash the MnO2 well with distilled water to remove the remaining acid and
dissolved salts.
Robert
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Sedit
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I have a Carbon monoxide tester in my house that will not stop going off. I can not find the source of CO yet I think its more then likely the heater.
I want to test to find out the source but I have no idea how I would go about identifing the source.
I need something that would react in the presence of large CO concentrations to preferably produce a color or something.
Any suggestions?
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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IrC
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Quote: Originally posted by Sedit ![](images/xpblue/lastpost.gif) | I have a Carbon monoxide tester in my house that will not stop going off. I can not find the source of CO yet I think its more then likely the heater.
I want to test to find out the source but I have no idea how I would go about identifying the source.
I need something that would react in the presence of large CO concentrations to preferably produce a color or something.
Any suggestions? |
I will assume you have a gas heater. Two causes are so hard to find it will drive you crazy. One is a crack in the burning chamber, not always visible
or easy to find. The other is rare and there must be a steady wind. If the top of the furnace exhaust vent is not high enough and the roof is shaped
just right a steady wind will drive monoxide back down the vent pumping it into the room. CO in the house is to me dangerous enough it is worth owning
a hand held probe. Also a gas detector.
http://cgi.ebay.com/Carbon-Monoxide-meter-CO-gas-meter-detec...
http://cgi.ebay.com/SPD202Ex-Combustible-Gas-Detector-Natura...
"Science is the belief in the ignorance of the experts" Richard Feynman
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Sedit
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Screwed up part is Im a third generation HVAC technician yet here I am looking for the source of the Carbon monoxide. Its not a cracked heat exchanger
like you suggested and I originally though because if so you would see a flutter in the flames of the heater.
I placed the carbon monoxide detector right on the heater which is also next to the water heater, the two prime suspects, and it stopped going off this in itself means im completely clueless now as to why this thing is going off
like mad everytime the air in the house settles such as when im home alone or when everyone is asleep...
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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vulture
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@ Magic Muzzlet
We use to make 3-methoxythiophene from 3-bromothiophene using similar conditions. It only works using freshly prepared NaOMe...
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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Magic Muzzlet
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Thanks for your input Vulture and I know it is meant to be freshly prepared, but the solid I got is not bromovanillin, so do you have any idea what it
could be?
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Sedit
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Does anyone know if Platinum plated electrodes would be good enough for the Kolbe electrolysis which calls for Pt ability to perform single electron
oxidations?
I have found dirt cheep Pt plated wire but dont know if it will work for a Kolbe electrolysis the way I desire. It shouldn't cause to much issue
should it since the final contact area is Platinum?
Side note: I found Jewlery that stated Rhodium as the material the pieces where made of,, much of it said rhodium and they are very cheep albeit
small, is this really rhodium plated like it says(somecases it dont say plated it suggest its pure) or is it some kind of jewlery talk?
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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Sedit
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Phosphorus help
Ok I got another question to ask of you all along with the one above.
I have a phosphate compound that goes by the brand name of Nu Calgon.
Im assuming its Sodium hexametaphosphate. When I heat it with a torch in both a stainless steel and a ceramic crucible to the point where it starts to
boil it releases some sort of flamable gas that pops with a green flame.
What is this that is igniting?
The only information I could find is that Sodium hexametaphosphate decomposes in a fire to phosphorus oxides and Sodium oxides but I kind of doubt
this is what im seeing.
I don't feel its phosphine either since water should be long gone by the time it reaches its boiling point.
Also when Aluminum is added to the melt it fizzes alot and I get a garlic smell but attempts to trap what I believe is White P fails.
Any suggestions on what this gas is? Even after it cools down when I break up the solid mass the trapped gasses still flare up on contact with air.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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not_important
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Nu Calgon is a company name, they have a number of products including 10 CL phosphate is is basically good old TSP; Calclean Special HD which is a
mixture including sodium polyphosphates and metasilicates and a few percent of high boiling organics; and a bunch more. Think you need to be more
specific.
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