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Random
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Is there a way to dissolve silver without HNO3?
I can make aqua regia but it will form insoluble silver chloride. No access to nitric though. Any alternative ways?
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DraconicAcid
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I suspect cyanide and oxygen would dissolve it nicely, but if you can't get nitric acid, then you probably can't get cyanide (and seriously, who wants
to work with cyanide?).
If you can make aqua regia, I suspect you're mixing a nitrate with hydrochloric acid. Can you mix the nitrate with sulphuric acid? Silver sulphate
is more soluble than the chloride.
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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UnintentionalChaos
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About 7.9g/L at room temperature. I would strongly hesitate to call that soluble.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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woelen
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If you have access to nitrates and sulphuric acid, then why not distill some to make HNO3 yourself? You should not make fuming HNO3, making a 60%
solution should do the trick. Just add water and KNO3 to H2SO4 and boil off the liquid at 120 C or so.
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PHILOU Zrealone
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If you don't have HNO3...then
Perchloric acid. Silver perchlorate is soluble.
Concentrated (not anhydrous) acetic acid alone with air (or maybe with some H2O2). Silver acetate is soluble and acetic acid dissolves the oxyde
layer.
NH4OH alone with air (or maybe with some H2O2). NH3 complexate Ag2O and dissolve the oxyde layer
Maybe NH4Cl with HCl or NH4Cl with NH4OH. AgCl is soluble in NH4OH and complexate.
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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bfesser
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<strong>Amos Backstrom</strong>, I strongly disagree with your statement about "making good nitric acid." It's quite simple, and an
apparatus can be improvised from basic kit—a florence flask, a glass tube, and a collection vessel submerged in ice are more than
satisfactory. A little care and forethought is required to carry out the procedure safely, but it's by no means difficult to obtain a product of
sufficient purity.
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woelen
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Distilling nitric acid requires an all glass apparatus with good seals. It is making the seals which make the setup difficult if you don't have a
distillation setup with ground glass joints. Using rubber or cork for joining tubes to each other is a no go with hot nitric acid vapors.
Dilute HClO4 does not dissolve silver. I can imagine though that dilute HClO4, mixed with H2O2 will do the job. If OP does not have HNO3, then I also
strongly doubt he has HClO4.
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Random
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Actually the only strong acid I have access to is HCl. So from all these options ammonia would be the best for me. If silver chloride complexes with
ammonia maybe I could make a soluble acetate from that complex and vinegar?
Silver and ammonia would have to get used fast though, I don't want that stuff exploding on me.
Now on obtaining silver chloride, would aqua regia work or would it just passivate my silver piece?
I was also thinking of electrolysis, maybe in vinegar?
Also I could make aqua regia with ammonium nitrate already, but I'm not sure if that is a safe option at all.
[Edited on 25-11-2013 by Random]
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deltaH
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Random, some food for thought:
You may be able to purchase sulfamic acid OTC as it is used as a descaler (check MSDS of brands available to you for composition confirmation). Silver sulfamate appears to be
fairly soluble, for example, see this silver sulfamate plating solution patent:
http://www.google.com/patents/US4279708
I couldn't find an exact solubility value for you, but that patent is somewhat indicative as they have an example using 60g/l (example 4).
You would still need an oxidant for the dissolution. I'm stuck on that as silver is an effective peroxide decomposition catalyst, so that may not be a viable means and I cannot think of a good non-nitrate alternative. I also don't
think peroxide and sulfamate can be safely paired.
Be aware that an electrochemical oxidation may not be straightforward. For starters, you could have your silver simply electroplating from anode to
cathode if the silver ions are not isolated between anolyte and catholyte 
On that note, salt bridges can be loads of chemistry fun. Perhaps experiment with preparing concentrated xanthan gum solutions using alkaline media and then gelling by mixing in concentrated sulfamic acid? I bought xantham gum from a health food shop
for dirt cheap.
In summary, the best non-nitrate suggestion for dissolving silver I can come up with would be some kind of electrochemical oxidation approach using
sulfamic acid and where you have isolated anolyte from catholyte.
[Edited on 25-11-2013 by deltaH]
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bfesser
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<strong>Amos Backstrom</strong>, I understood what you meant. I disagree. For preparing AgNO<sub>3</sub>, 50–60%
HNO<sub>3</sub>(aq) should be just fine. If it's too concentrated, the silver will dissolve slowly, if appreciably (passivation, limited
solubility, etc.). Preparation of nitric acid and it's use in preparing silver nitrate is one of those topics which has been discussed <em>ad
nauseam</em>. I suggest you try searching the fora and reading through what's already been written on the subject before asking more questions.
I think you'll find that all of your questions have already been answered.
[edit] <strong><a href="viewthread.php?tid=25328">Silver Nitrate Synthesis</a></strong>
[Edited on 25.11.13 by bfesser]
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clearly_not_atara
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http://anonym.to/https://answers.yahoo.com/question/index?qi...
diammine silver (I) chloride. AgCl (s) + 2NH3 (aq) --> Ag(NH3)2+ (aq) + Cl- (aq)
and I did in fact link yahoo! answers. in my defense i just remembered the complex name diamminesilver (I) and googled it.
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phlogiston
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Alternatively, you can dissolve the silver chloride in sodium thiosulphate solution.
Here is an interesting overview of solubilities:
http://www.saltlakemetals.com/Solubility_Of_Silver_Chloride....
A -long- time ago, when had no acces to nitric acid, I prepared a small sample of lead nitrate by dissolving metallic lead in molten ammonium nitrate.
Perhaps the same works with silver, but do study the dangers of melting ammonium nitrate before you consider this (especially if you were to try this
on more than a very small scale).
-----
"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer |
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Paddywhacker
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Silver will dissolve in liquid mercury, and also in molten copper or gold.
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aga
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Is that pirahna solution on steroids ?!?!
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woelen
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Dilute HClO4 with H2O2 is not energetic or explosive at all. It is a mild oxidant. Dilute HClO4 is not oxidizing at all. I have done experiments with
boiling 60% HClO4 and this liquid is not capable of oxidizing iodide to iodine or sulphur dioxide to sulfate. Zinc does dissolve in this, but only
with formation of hydrogen gas (the acid part is the oxidizer, not the perchlorate part).
Piranha solution only is formed with nearly anhydrous conditions, i.e. conc. sulphuric acid with highly concentrated H2O2. It is a misconception to
think of dilute acids with H2O2 as piranha solution.
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quantumcorespacealchemyst
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How about H2SO4 with KNO3 and Sodium acetate?
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blogfast25
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That would probably work but I don't see the point to the acetate.
The solubility limit of Ag2SO4 will reached regardless of acetate ions being present.
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nezza
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Concentrated sulphuric acid with heat will dissolve silver. For dilute acids an oxidising agent is required. Dilute sulphuric acid with hydrogen
peroxide should dissolve silver. Nitric acid is by far the easiest way to get silver into solution though.
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quantumcorespacealchemyst
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Will the H2SO4 turn to 4K2SO4 with the NO3- going to Ag+ with the H+ going to H2 gases? I don't understand about the solubility limit of Ag2SO4 being
reached. With the acetate, I was/am wondering about claiming AgOOCH3.
does KMnO4 + H2SO4 + Acetate/Acetic Acid destroy the Acetate ion. I am wondering about this for Ag, preferably from shot form (also Au and Hg {I read
KMnO4 and H2SO4 dissolves gold but no salt is formable due to the instability of gold sulfates [on a refining forum]. I was unsuccessful so far, and
have yet to test stronger acid and/or oleum})
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clearly_not_atara
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I can get to diamminesilver nitrate: EDIT -- all the way to silver nitrate, see bottom.
Silver sulfate + ammonia + Ca(NO3)2 (in water) >> CaSO4 (s) + Ag(NH3)2+ (aq) + NO3- (aq)
I don't have any idea how to get AgNO3*2NH3 to turn back into AgNO3. Heating will almost surely result in the reduction of silver and possibly
explosive decomposition of the nitrogen compounds.
One possibility is to add silver (II) oxide to decompose ammonia. This is usually produced, again, from silver (I) solutions.
You can probably prepare some silver salts from this solution -- excess acid should break the Ag-N bond. Acetic acid will precipitate silver acetate,
which can be used to make acetic anhydride. Boric acid should give silver borate. Toluenesulfonic acid, the tosylate.
EDIT: this paper says that diamminesilver slowly decomposes in warm solutions to liberate ammonia gas:
http://pubs.rsc.org/en/content/articlelanding/1975/an/an9750...
[Edited on 5-5-2016 by clearly_not_atara]
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Sulaiman
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getting silver into an aqueous solution ... for what purpose ?
silver nitrate is a useful reagent, a precursor to many silver compounds which themselves are mostly insoluble.
So if a route is available for you I think that it is worth the effort to make silver nitrate.
ionic and colloidal silver solutions can be made by electrolysis of distilled water with silver electrodes.
ionic up to 20 ppm so not 'soluble' by any common definition 
notes:
Silver nitrate stains work surfaces and skin and can melt your corneas,
wear goggles & gloves (silver nitrate seems to go through latex gloves)
or, I use goggles and no gloves and rinse my hands with sodium thiosulphate solution before exposing to any sunlight.
I also used sodium thiosulphate to minimise any silver nitrate stains when I used the kitchen.
many silver compounds are light sensitive - especially when impure.
EDIT: if you do not have sodium thiosulphate do not do silver chemistry where stains are a problem !
[Edited on 5-5-2016 by Sulaiman]
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macckone
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Silver nitrate is not known to 'melt corneas'.
In fact solutions of silver nitrate are used as eye drops in newborns.
Any salt directly in the eye will be unpleasant unless diluted.
The most dangerous chemicals for your eyes are still strong acids and
bases. However brake cleaner will eat contact lenses and that can also
be unpleasant.
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Sulaiman
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1% silver nitrate used as Credé's Prophylaxis for newborns is, I believe, immediately followed by saline rinse,
converting caustic silver nitrate to silver chloride.
DO NOT GET SILVER NITRATE IN YOUR EYES, EVEN A TINY BIT.
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clearly_not_atara
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ALWAYS wear eye protection when doing any chemistry. This shouldn't be a question, even if the reaction is just salt metathesis.
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AJKOER
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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]
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