clearly_not_atara
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Dissolving silver as silver lactate?
https://www.americanelements.com/silver-lactate-128-00-7
| Quote: | | Solubility in water: 77 grams/liter |
That's not very high, but it's significantly higher than any silver salt not based on nitrate, perchlorate, or a fluorinated anion. Lactic acid is
very OTC, and silver lactate is 7x as soluble as silver acetate.
So it seems like an attractive source of soluble silver for preparing other silver salts by salt metathesis, no?
I know there's a sticky, but Ag(CO2COH2CH3) hasn't been mentioned in there.
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zwt
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Sulfamic acid may be a good candidate as well. The following is silver sulfamate solubility, in grams per 100 grams of water, from Lange's
Handbook of Chemistry, 14th Edition.
<table
style="width:60%"><tr><th>Temp</th><th>0°</th><th>10°</th><th>20°</th><th>30°</t
h><th>40°</th><th>50°</th><th>60°</th></tr><tr><td>Silver sulfamate
(g/100g)</td><td>2.30</td><td>4.82</td><td>7.53</td><td>10.3</td><td>15.3</td><td
>* </td><td>28.5</td></tr></table>
(Sulfamic acid was suggested by deltaH in one of the threads linked from the stickied thread.)
I've personally found sulfamic acid OTC at hardware stores, but I've never seen lactic acid as a standalone product OTC (though I'm sure it's
available at certain specialty shops). I couldn't find any detailed solubility data for silver lactate; sorry if I'm derailing the thread.
[Edited on 6-10-2016 by zwt]
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Texium
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Lactic acid is usually available at homebrewing shops as an 85% solution.
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DraconicAcid
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You will only ever see it as an 85% solution, or more dilute, even from Aldrich, etc.
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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zwt
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I wonder what this powder really is: "INGREDIENTS: Lactic Acid."
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DraconicAcid
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Weird. I thought it was unobtainable as a solid.
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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zed
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Well, I like the idea well enough, but I'm concerned about NaCl content.
In most Lactic Acid applications, strict exclusion of the Chloride ion might not be considered important. For us, exclusion of the Chloride Ion is
very important.
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AJKOER
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You could try adding Silver metal to a source of Lactic acid mixed with dilute H2O2 and a touch of KNO3 (acting as an electolyte in this
electrochemical dissolution of Silver).
Jump start the reaction by heating in a microwave.
In under 10 minutes, you should know whether this suggested path is working!
Basically, you would be paralleling my sucessful attempt of dissolving Ag in a mix of dilute H2O2 and vinegar with a touch of KNO3. See, for example,
http://www.sciencemadness.org/talk/viewthread.php?tid=69061#... and links cited.
If you have no access to KNO3 usually sold as a tree stomp remover, then try NaHCO3 (can't remember if I actually did try using baking soda).
----------------------------------------------------------------------
Note, I said a source of Lactic acid which may come from a home brew of whole milk plus some bacteria rich yogurt (no experience here as I gave up on
milk for a milk substitute as it just goes sour too quickly).
[Edited on 9-10-2016 by AJKOER]
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Texium
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The only way that could actually be pure lactic acid and a
solid, assuming the picture is taken at a reasonable room temperature, is if it is enantiomerically pure... the racemic mixture melts at 17ºC.
Doesn't seem right, but it could be that it's produced using a process like this: http://link.springer.com/article/10.1007/s10529-007-9408-4 They do say that it's produced from beet sugar. Maybe it's pure D-lactic acid.
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nezza
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The thing is silver is well below hydrogen in the electrochemical series so will not displace it from a non-oxidising acid. Sulphamic acid would be a
good choice as it is a strong acid with a soluble silver salt but an oxidising agent will still be needed to get the silver into solution. Once
dissolved it can be precipitated as carbonate and then dissolved in any of the weaker acids.
If you're not part of the solution, you're part of the precipitate.
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unionised
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IIRC silver tartrate decomposes- the silver oxidises the tartrate ion.
I can see the same thing happening here.
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