Pages:
1
..
13
14
15
16
17
..
104 |
elementcollector1
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 2684
Registered: 28-12-2011
Location: The Known Universe
Member Is Offline
Mood: Molten
|
|
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.
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
|
|
papaya
National Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 615
Registered: 4-4-2013
Member Is Offline
Mood: reactive
|
|
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.
|
|
Etaoin Shrdlu
National Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 724
Registered: 25-12-2013
Location: Wisconsin
Member Is Offline
Mood: Insufferable
|
|
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.)
|
|
Brain&Force
Hazard to Lanthanides
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1302
Registered: 13-11-2013
Location: UW-Madison
Member Is Offline
Mood: Incommensurately modulated
|
|
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...
|
|
alexleyenda
Hazard to Others
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 277
Registered: 17-12-2013
Location: Québec, Canada
Member Is Offline
Mood: Busy studying chemistry at the University
|
|
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
|
|
papaya
National Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 615
Registered: 4-4-2013
Member Is Offline
Mood: reactive
|
|
Quote: Originally posted by Brain&Force ![](images/xpblue/lastpost.gif) | 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.
|
|
Brain&Force
Hazard to Lanthanides
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1302
Registered: 13-11-2013
Location: UW-Madison
Member Is Offline
Mood: Incommensurately modulated
|
|
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...
|
|
Nickdul
Hazard to Self
![*](images/xpblue/star.gif)
Posts: 96
Registered: 13-2-2012
Location: Bulgaria
Member Is Offline
Mood: No Mood
|
|
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]
|
|
bismuthate
National Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 803
Registered: 28-9-2013
Location: the island of stability
Member Is Offline
Mood: self reacting
|
|
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?
|
|
Zyklon-A
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
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?
|
|
confused
Hazard to Others
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 244
Registered: 17-3-2013
Location: Singapore
Member Is Offline
Mood: tired
|
|
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
|
|
Zyklon-A
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
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.
|
|
thebean
Hazard to Others
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 116
Registered: 26-9-2013
Location: Minnesota
Member Is Offline
Mood: Deprotonated
|
|
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
|
|
Zyklon-A
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
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.![:mad:](./images/smilies/mad.gif)
I think the Teflon will work, I have stored chlorine before for about 3 months in a vial, as mentioned here.
|
|
jock88
National Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 505
Registered: 13-12-2012
Member Is Offline
Mood: No Mood
|
|
at Nickdul
|
|
alexleyenda
Hazard to Others
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 277
Registered: 17-12-2013
Location: Québec, Canada
Member Is Offline
Mood: Busy studying chemistry at the University
|
|
Quote: Originally posted by bismuthate ![](images/xpblue/lastpost.gif) | 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]
|
|
DraconicAcid
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 4299
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
Quote: Originally posted by alexleyenda ![](images/xpblue/lastpost.gif) | Quote: Originally posted by bismuthate ![](images/xpblue/lastpost.gif) | 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.
|
|
alexleyenda
Hazard to Others
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 277
Registered: 17-12-2013
Location: Québec, Canada
Member Is Offline
Mood: Busy studying chemistry at the University
|
|
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
|
|
elementcollector1
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 2684
Registered: 28-12-2011
Location: The Known Universe
Member Is Offline
Mood: Molten
|
|
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
Latest Acquired: Cl
Next in Line: Nd
|
|
Nickdul
Hazard to Self
![*](images/xpblue/star.gif)
Posts: 96
Registered: 13-2-2012
Location: Bulgaria
Member Is Offline
Mood: No Mood
|
|
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.
|
|
Zyklon-A
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
Keep it, I regret selling all of my silver.
|
|
Zyklon-A
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
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]
|
|
S.C. Wack
bibliomaster
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 2419
Registered: 7-5-2004
Location: Cornworld, Central USA
Member Is Offline
Mood: Enhanced
|
|
Sand. Glass wool.
|
|
DraconicAcid
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 4299
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
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.
|
|
Zyklon-A
International Hazard
![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif) ![*](images/xpblue/star.gif)
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
Ok, thanks. I don't have any glass wool, non do I have pure sand. I'll use a pipette.
|
|
Pages:
1
..
13
14
15
16
17
..
104 |