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  1. #1

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    Chemistry question

    I'm not a chemist but I have had 2 years of chemistry in HS and did play around with a chemistry set as a kid.

    Will only nitric-ish?-acids-with-silver (silver nitrate) precipitate silver halides? Or can other types of silver acids do that too?

    Thanks
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  2. #2
    Ian Grant's Avatar
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    Only nitric acid.

    Ian

  3. #3
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    Actually, you could use Silver Acetate or Silver Sulfate among others. The correct term is Silver salt of an acid. All you need is to prepare a soluable Silver + Y salt (Y being any suitable acid that makes a soluable Silver salt). However, historically, Silver Nitrate has been found to be the best.

    PE

  4. #4
    Ian Grant's Avatar
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    That's true but Silver doesn't dissolve in Acetic or Sulphuric acid

    Usually to form other salts combinations of acids are used, or a silver cyanide is acidified, which is potentially lethal, and not to be tried.

    Ian

  5. #5

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    About four years ago I was able to produce (what appeared to be) silver chloride using saltwater, coin silver and a 30V DC power source via electrolysis. The result looked like a layer of milk under the saltwater. I removed the excess saltwater and coated ordinary paper with it. Within a few seconds under sunlight it turned a very dark purple. As I recall, the most difficult part of the experiment was getting the correct concentration of salt to water. I made a couple small photograms with keys and leaves, now lost in a book that I can't find. But it was a fun experiment. Were halides produced? Not sure. I'm not a chemist either.
    "Lo único de lo que el mundo no se cansará nunca es de exageración." Salvador Dalí

  6. #6

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    DannL, yes, you made silver chloride.

    Ian, he's not asking what acids dissolve silver, but what silver salts can be used to precipitate silver halides.
    Kirk

    For up from the ashes, up from the ashes, grow the roses of success!

  7. #7

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    Cool! So new question now - After one gets a viable silver halide (ie the silver salt precipitates to halide which is photon sensitive):

    - Then a photon strikes the halide which bumps an electron up to a higher orbital?

    - When developed, the halide gives up an electron and drops back down into a visible silver salt?

    That is a neat experiment - thanks for sharing!

    Thanks!
    Last edited by WolfTales; 08-23-2009 at 10:42 AM. Click to view previous post history.
    I brake for fixer!

  8. #8
    Ian Grant's Avatar
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    Yes silver can form silver chloride quite easily but then this forms a coating that prevents the process going further.

    Ian

  9. #9

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    Quote Originally Posted by Ian Grant View Post
    Yes silver can form silver chloride quite easily but then this forms a coating that prevents the process going further.

    Ian
    Well - my question is how the overall chemical mechanism works, not how one variable may stop the process.
    I brake for fixer!

  10. #10
    Ian Grant's Avatar
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    Sorry I was answering DannL's point, but by the time I finished eating my evening meal you & Kirk had posted

    There's an excellent Kodak film (video) online about how film is made and how the whole process works, someone posted a link to it a few weeks ago. It's well worth watching as it's talked about in laymans terms and explains excatly what you're asking. Sorry I can't remember the link.

    Ian

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