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elementcollector1
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I know about the passivation from concentrated nitric acid, but what about dilute? Copper metal seems to follow much the same rules, and it reacts
vigorously when in *dilute* nitric acid.
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papaya
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I'm afraid even dilute acid won't work.
https://en.wikipedia.org/wiki/Al%28NO3%293
I can't figure out any clean route myself. Maybe if Al(OH)3 is obtained first, it could be dissolved in HNO3? But hydroxide is a gel as far as I know
and will entrap all kind of ions (if for example obtained by AlCl3 + NaOH route) inside.
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Etaoin Shrdlu
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Question
methyl anthranilate + undecanal --> Schiff base
Is there any simple chemical method to check for the presence of leftover reactants? Short of a GC analysis I'm stumped. (Yes, I know they'll be
there.)
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Brain&Force
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papaya, dissolve it in HCl first, then add an excess of nitric acid to the aluminum chloride. The acidic solution of nitrate and chloride will convert
to nitrosyl chloride, and eventually there will be no more chloride in solution, just nitrate. Do it in a fume hood for safety.
Or why not make aluminum carbonate?
At the end of the day, simulating atoms doesn't beat working with the real things...
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alexleyenda
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A little bit out of subject, but I have to tell it, it is too funny: The first time I read your message ( I am very tired tonight and english is not
my first language so I make connections slowly, and I didn't read the previous posts before ), I thought you told someone to dissolve a papaya in HCl
and add HNO3 to the produced aluminium chloride etc... and I was really strongly thinking what the hell, meditating in front of my screen, trying to
understand XD I had never seen that someone is called papaya before. I laughed a lot when my brain decided to go back to work :p
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papaya
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Quote: Originally posted by Brain&Force  | papaya, dissolve it in HCl first, then add an excess of nitric acid to the aluminum chloride. The acidic solution of nitrate and chloride will convert
to nitrosyl chloride, and eventually there will be no more chloride in solution, just nitrate. Do it in a fume hood for safety.
Or why not make aluminum carbonate? |
AlCl3 + nitric acid looks interesting, if you are absolutely sure that it will work. Do I need anhydrous AlCl3 and conc. HNO3 or aqueous solutions
will do? Is it that easy to get rid of all chloride or it'll be still impure? Some details (or references) please.
Also I thought Al carbonate cannot be made from water solutions since it'll tend to hydrolyze , wiki is not clear about that
https://en.wikipedia.org/wiki/Aluminium_carbonate
but if it works (Na2CO3 + Al salt) then I would like to go this way.
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Brain&Force
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https://www.youtube.com/watch?v=u4Ha1SJrazY
Just keep the solution acidic.
At the end of the day, simulating atoms doesn't beat working with the real things...
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Nickdul
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Does sodium/potassium metabisulfite degrade over time (say, 2-3 years), releasing SO2 and leaving behind the sulfite? I have a bank of
K2S2O5 that has gotten quite lumpy and hard to dissolve in water.
Also, S2O5 + H2O -> 2HSO3 in solutions. Does any other anion, other than the bisulfite, exist in
aqueous solution? I'll be buying new metabisulfite, but I wonder if it's also worthwhile to get what is sold as bisulfite (how can it be a dry
powder?).
[Edited on 18-2-2014 by Nickdul]
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bismuthate
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I tried the briggs-rauscher oscillating iodine reaction but I replaced the H2SO4 with a stoichiemetric amount of NaHSO4. The mixture did nothing why
is this?
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Zyklon-A
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Question
Does chlorine attack rubber stoppers?
For my element collection I have decided to store some chlorine now. I'm putting it in a big test tube, so the color will be visible, but will it
disintegrate the stopper over time?
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confused
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yes, it'll cause the rubber to become brittle and eventually disintegrate the stopper, you might want to ampoule it, i recommend practicing a few
times before storing the sample
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Zyklon-A
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Well I can't ampule it, but I have a roll of Teflon tape, So I'll rap the stopper with a few layers of that.
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thebean
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Honestly for something like chlorine the only way I would say you can safely store and be completely comfortable is ampouling. You can make an ampoule
using a glass pipette. I know NurdRage has a video on it but I can't link to it right now.
"You need a little bit of insanity to do great things."
-Henry Rollins
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Zyklon-A
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I know I've seen the video, I need all my glass pipets right now, getting an ampule isn't the problem either, sealing it is, my torch recently
broke.
I think the Teflon will work, I have stored chlorine before for about 3 months in a vial, as mentioned here.
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jock88
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at Nickdul
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alexleyenda
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| Quote: Originally posted by bismuthate | | I tried the briggs-rauscher oscillating iodine reaction but I replaced the H2SO4 with a stoichiemetric amount of NaHSO4. The mixture did nothing why
is this? |
This reaction includes many equilibrium reactions that must all take place for the reaction to succeed. Quote from wikipedia "IO3− + 2H2O2 +
CH2(COOH)2 + H+ → ICH(COOH)2 + 2O2 + 3H2O"
NaHSO4 being a neutral salt, it does not provide the H3O+ ions needed for the step cited above.
[Edited on 19-2-2014 by alexleyenda]
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DraconicAcid
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| Quote: Originally posted by alexleyenda | | Quote: Originally posted by bismuthate | | I tried the briggs-rauscher oscillating iodine reaction but I replaced the H2SO4 with a stoichiemetric amount of NaHSO4. The mixture did nothing why
is this? |
This reaction includes many equilibrium reactions that must all take place for the reaction to succeed. Quote from wikipedia "IO3− + 2H2O2 +
CH2(COOH)2 + H+ → ICH(COOH)2 + 2O2 + 3H2O"
NaHSO4 being a neutral salt, it does not provide the H3O+ ions needed for the step cited above. |
Incorrect. NaHSO4 is hardly a neutral salt, being more acidic (Ka = 1 x 10-2) than phosphoric acid (K1 = 7 x 10-3). However,
because it's not a strong acid, the solution will not be as acidic as a solution of sulphuric acid, which means that reactions that have hydronium ion
in their rate law will go at a much different rate, thus mucking up the expected oscillation.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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alexleyenda
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My bad, it is sodium sulfate that is a neutral salt, I confused both. At least I had part of the answer  By the way I salute your knowledge Draconic, you always have the righ precise and well explained answer to everything
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elementcollector1
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Not really an information-seeking question, more an opinion-seeking one.
I have a 1 troy oz. bar of .999 silver. I want to cut off a bit and put it in an ampoule. However, doing so would make me unable to sell the bar as
anything other than bulk silver (which I guess is not so bad, but collector's value can be a powerful thing). Should I use this bar as my source for
silver, or should I obtain it from another source and use that?
Bar is Pan American, and was bought about 5-6 years ago.
Elements Collected:52/87
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Nickdul
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My opinion would be to keep it as an investment. If it is for an element collection, 1g bars are going for a decent price and (again, my opinion) are
very cute  The same goes for 1g gold bars.
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Zyklon-A
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Keep it, I regret selling all of my silver.
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Zyklon-A
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Filter nitric acid
I made some dilute nitric acid according to this reaction:
Ba(NO3) + H2SO4 → 2HNO3 + BaSO4 ↓.
(26.1 g Ba(NO3) + 9.9 g H2SO4 + 7.0 g H2O → 23.3 g BaSO4 ↓ + 12.6g HNO3
+ 7 g H2O.)
12.6g HNO3 + 7 g H2O = 19.6 g 66.3% HNO3 = .2 mol HNO3.
So my question is, How can I filter off the barium sulfate?
I have disposable coffee filters, a synthetic filter, and a filter made out of copper mesh.
Obviously, the copper will react, but would a disposable coffee filter work? Or will it react, I know con. sulfuric acid reacts with paper. There is
slight excess sulfuric acid, because I wanted to make sure that all the nitrate would react, and form insoluble sulfate. Nitric acid + sulfuric acid
+ cellulose → potential nitrocellulose? Would that happen with 66% nitric acid and ~2% sulfuric acid?
[Edited on 27-2-2014 by Zyklonb]
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S.C. Wack
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Sand. Glass wool.
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DraconicAcid
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Or let it settle, and remove it with a pipette.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Zyklon-A
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Ok, thanks. I don't have any glass wool, non do I have pure sand. I'll use a pipette.
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