Silver contacts

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Rreyes097

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Nitric acid and distilled water with a little heat I've been dissolving silver contacts. Now I've run into a problem where the silver contacts simply do not want to dissolve. Heat more acid more water and nothing! I also double check just now one of the contacts which looks to not been melted much at all if any. I tested it with silver testing solution. And it was bright red indicating it is indeed silver. Could anyone tell me what the problem with this is? Am I just being impatient or are there some cases where the silver will not dissolve?
 

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Yggdrasil

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I do not think "melted" should be used here.
You are dissolving in acid, not heating until liquid.
When dealing with the complex and dangerous
procedures of refining, it is wise to use
precise language.
As to the contact points, some are sintered with among other things Tungsten.

These things has been mentioned over and over again, so do a search, please.
 

Palladium

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I think your problem is solution volume. Contacts are like a honey comb with the silver between the pressed materials. The more you dissolve the deeper the solution has to go to get to the silver. This is controlled by a couple of parameters. Heat drives the solution deeper in the substrate. The further along you get the hotter and more angrier the solution must become to penetrate ( heat = speed= distance traveled). The second thing is solution volume. The larger the volume of the solution becomes the further the ions (nitric) in the solution must travel to find their mark. Traveling the extra distance can be somewhat overcome with heat as the driving force. It can also be overcome by addition of more and stronger ions (nitric), but the more ions you add the more the solution volume increases. It's a trade off though, there comes a point when all these things just won't perform. Pour off what you have now and add it to your other solution where you leached the silver for precipitation. Add fresh nitric, but don't dilute it this time. Dilution is really to stop the precipitation of salts when it cools. If it's 69% nitric then it already has 31% water. The stronger less dilute nitric will finish the job nicely.

Use a catch basin! The jar scares me! Look on the forum for the word Pyroceram.
 

Topher_osAUrus

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Palladium said:
...
Use a catch basin! The jar scares me! Look on the forum for the word Pyroceram.

That was my first thought. That the jar looks super sketchy on that ...layer of rocks and boulders?...
 

Rreyes097

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It's dirty sand. And thanks for the advice. Also if these things have been mentioned over and over again I haven't seen it hence the reason why I'm asking the question. This does not mean I have not done any studying. I have read and read, posts on silver and anything else that I am working on at the time.
 

Rreyes097

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I have silver precipitated from copper. Is that called silver oxide or nitrate? Well either way I have a little bit of that in a beaker. Along with what looks like silver chloride. Is this possible and if so how do I get the silver chloride to match the other silver? Do I still do the sugar and lye? And if it's not silver chloride and something else precipitated such as lead or something will the sugar and lye method mess things up?
 

Martijn

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Metal. Lye and sugar will do.
For a 5 year long member with 180 posts you sure ask a lot of questions that can be found by using the search button.
Displacement of metals from solution is basic knowledge used in waste treatment.
Was the cloudiness there before you started cementing?
Did you filter the AgNO3 solution first?
 

Rreyes097

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Martin, first of all your more then welcome to not respond to my questions. No matter how many there are. And secondly I haven't been doing this for 5 years. I did it for a year or so then stopped for 3 years. There wasn't any cloudiness. Just the precipitation looks like regular grey/silver color speckled with white. Not much but just barely noticeable. And once again I have searched and read plenty. Yes I didn't search on this one question. But I learn better having a comprehensive conversation with people who say they know more than I do on said topics. Yes I can research and research until the sun goes down but sometimes my situational questions aren't going to be found in the search function. But yes in this particular situation may be found under the search function but I didn't to take the time to do that to be honest. But only this time. Every other time I have searched before asking. I have seen many of your guys's responses telling people to research first and I have learned to do that. But failed to do this time. My bad. I just wanted to make sure that if this was silver chloride mixed with my nitrate that sugar and lie would not hurt my nitrate.
 

Topher_osAUrus

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I have silver precipitated from copper. Is that called silver oxide or nitrate? Well either way I have a little bit of that in a beaker. Along with what looks like silver chloride. Is this possible and if so how do I get the silver chloride to match the other silver? Do I still do the sugar and lye? And if it's not silver chloride and something else precipitated such as lead or something will the sugar and lye method mess things up?
That is elemental silver. Copper replaces the electrons in the oxidized silver, making copper nitrate and elemental (metallic) silver as your cemented solid

No need for sugar and lye. -that is what converts silver chloride to elemental silver

Now, if by some chance there ended up being any turbidity in your silver nitrate solution at all (i mean, a bit milky looking....anything except crystal clear when checked w a laser) it could very well be silver chloride from some chlorine contaminants...water, used wrong filter, even had the vessel open next to a bit of HCl--all of these have caused me grief in the past.

Lead is sparingly soluble in hot water, as is silver chloride.
That being said, they should be removed during the wash/rinse/boil process of your cemented (elemental) silver.

...sorry if i omitted or missed anything. The new forum layout leaves much to be desired. Ill get used to it with time
 
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