chemkid
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Dissolving Silver
Nitric acid is in no abundance here and i don't really want to deal with nitrogen oxides and delayed pulmonary enema to dissolve silver. I could buy
silver nitrate, but i have perfectly good silver scrap right here. I considered heating with sulfur to make silver sulfide and dissolving in acid,
but that would bring H2S into the picture, also not eager to play with.
I found two methods: a silver thiosulfate solution or an acidified potassium permanganate solution. Any recommendations on which is better to use or
another method?
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The_Davster
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What silver salt do you want in the end? Nitrate is the best for solubility reasons.
Electrolysis in a divided cell with KNO3 solutions could be used, but anolyte and catholyte must be separate, you would end up with a silver nitrate
solution in the anolyte, that had KNO3 in solution, which may be acceptable to you, or fractional crystallization could be done.
As for the permanganate method you must consider what you would acidify with if you do not have nitric acid, as any silver that began to dissolve in
such a solution would precipitate with most of the common acids used. The instantaneous precipitation of silver salt may passivate the metal.
Just checking some ksps acetic acid might be all you could acidify with, as silver acetate is relatively soluble compared to things like chloride or
sulfate. ksp=2E-3
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ShadowWarrior4444
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As I accidentally discovered in my previous experiment, posted here, silver can be electolytically dissolved into an organic complex; this procedure
may help you to find agreeable means of doing so yourself:
http://www.sciencemadness.org/talk/viewthread.php?tid=10700
I have not run any chemical tests on the complex at this time, however I suspect it can be identified in solution as a pale-white/grey translucent
solute. Care must be taken to prevent its destruction at the cathode.
Additionally, I should mention that membrane cells are hilariously easy to construct; a latex/latex substitute glove can work as a membrane, as can a
non-glazed ceramic pot. Flower pots are preferable, especially the orange-esque ceramic version; the hole in the bottom must be plugged with a
non-reactive substance, wax is likely preferable.
I tend to like modifying PETE bottles for use as electrolytic cells for proof-of-concept testing and the like. A good rotary tool and various kinds of
epoxy/contact sealant are very useful for a home, and do wonders to turn discarded water bottles into miniaturized industrial plants. Irrigation
valves and pipes are fun too.
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