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PHILOU Zrealone
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Quote: Originally posted by AJKOER  | Try microwaving a mix of elemental silver (or Sterling silver which is Ag mixed with Cu) with 3% H2O2, 5% acetic acid (vinegar) and a very small
amount of sea salt (which acts initially as an electrolyte for this electrochemical based dissolution reaction) to form a dilute solution of soluble
silver acetate (and some copper salts with Sterling silver).
As to why the Silver acetate is soluble, I refer the reader to "The Effect of Some Salts on the Solubility of Silver Acetate and of Silver Nitrate in
Acetic Acid at 30°", by Ralph K. Birdwhistell, ...with the 1st page available at http://pubs.acs.org/doi/abs/10.1021/ja01609a016?journalCode=...
My take: the NaCl reacts with some of the created AgAc forming AgCl and sodium acetate, with the latter apparently extending the solubility of AgAc in
acetic acid in dilute solutions per the article.
[Edited on 8-8-2016 by AJKOER] |
And what happens with the cementation reaction?
2 Ag(+) + Cu(s) --> 2 Ag(s) + Cu(2+)
Cu metal is more electropositive than Ag and thus displace it from its salts...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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AJKOER
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Sterling silver is an alloy of silver containing 92.5% by weight silver and 7.5% other metals, usually copper.
I suspect the Cu dissolves faster in vinegar/H2O2 than does the Ag, so the reaction:
2 Ag(+) + Cu(s) --> 2 Ag(s) + Cu(2+)
over emphasizes the likely presence of freshly created silver. But, if formed, it quickly reacts with the excess vinegar/H2O2. That is, one does not
leave a large piece of Sterling silver in a solution devoid of acetic acid/H2O2. The final products are acetates of both metals.
Separation of respective Ag/Cu salts a bit off topic, but one could start by adding a sheet of copper metal.
[Edited on 9-8-2016 by AJKOER]
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NEMO-Chemistry
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I have managed to find a cheap source of silver! As most of you dont live near me i dont mind sharing  .
I went looking around charity shops (shrift shops in the states i think), and alot of the lower end ones sell old cutlery. If you delve through the
trays you can often find silverware very cheaply!
I managed to find 24 various items like knives and forks for around 5p each!! Some are plated but some simply say sterling silver with a hallmark on.
I have no idea how much silver is in them but it must be worth it for the price!
It at least should give me a reasonable amount of silver nitrate once i have recovered the silver.
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alive&kickin
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NEMO, sterling silver is a jewelry standard of 92% silver with 8% copper. You've got a bit of silver there.
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clearly_not_atara
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I posted a thread about silver lactate earlier, which has roughly seven times the solubility of silver acetate (without help). Silver sulfamate has
also come up as having similar solubility. I believe that silver can be dissolved in either acid with the help of a little H2O2. However, there were
some concerns about the stability of silver lactate, although I have yet to find a reference suggesting that it autooxidizes, and the hydroxyl group
is more electron-deficient than a typical alcohol because of the electron-withdrawing effect of the carboxyl group, so it might not.
However, there's still room to improve on this, since neither salt is as soluble as silver fluoride or silver nitrate, which are both very soluble but
involve using dangerous HF or HNO3. Tetrafluoroborate, hexafluorophosphate, and triflate are also highly soluble, but very hard to obtain, of course.
http://en.wikipedia.org/wiki/Oxamic_acid
^but this might not be. Silver oxamate may have an even higher solubility than the lactate, since oxamic acid can form more hydrogen bonds than
lactate. Oxamic acid is as easy to synthesize as just heating monoammonium oxalate And of course the amide group is much less oxidizable.
EDIT:
https://books.google.com/books?id=xR86AQAAIAAJ&pg=PA56&a...
Paper title: "Decomposition of Bioxolate of Ammonia by Heat" -- I think you know where this is going
| Quote: | | A solution of oxamate of ammonia and oxamate of baryte, treated with nitrate of silver, furnished an abundant gelatinous mass, demi-transparent, and
which soon becomes opaque. This precipitate is completely dissolved in the liquor when we raise the temperature,
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(bold mine) It actually may be quite soluble, although not as soluble as the ammonium salt or AgNO3
[Edited on 20-1-2017 by clearly_not_atara]
[Edited on 20-1-2017 by clearly_not_atara]
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DraconicAcid
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I wonder how soluble silver glycinate is....
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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PHILOU Zrealone
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Glycolate?
Tartrate?
Formate?
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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clearly_not_atara
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http://pubs.rsc.org/-/content/articlelanding/1904/ct/ct90485...
Paper states that silver oxide and alkyl iodides can be used together to esterify oxamic acids, with the example used being oxanilic acid
(N-phenyloxamic acid). It seems likely that this involves a silver salt intermediate, since alkyl iodides would normally react with Ag2O to give
ethers or alcohols, IIRC.
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