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Can you gold plate a penny using gold nitrate?

  1. Dec 21, 2009 #1
    Just like the experiment in high school using zinc powder and sodium hydroxide, is there a way to use real gold plating with out having to melt real gold. Such as gold nitrate? Is gold nitrate rare, expensive or dangerous? Thanks!
     
  2. jcsd
  3. Dec 21, 2009 #2

    turbo

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    If you want to gold-plate a penny, you can do so by electroplating it. You will need a pretty strong acid to get the gold into solution, though, so you'll have to be cautious.

    Edit: Gold chloride may be an acceptable salt for electroplating.
     
    Last edited: Dec 21, 2009
  4. Dec 21, 2009 #3

    chemisttree

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    Electroless gold works great for this. Google "electroless gold".
     
  5. Dec 22, 2009 #4

    DrDu

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    The problem is to obtain a lustrous cover of gold. To that end the effective concentration of gold has to be very low. One usually achieves this working with a solution of cyanidic gold complexes which release only very little gold ions. But these are very toxic.
     
  6. Dec 22, 2009 #5
    Thanks a lot everyone for your insight. This helps a lot! What about silver plating? or Silver Nitrate? With the silver nitrate growing crystals on copper wire experiment could this be achieved with a small plating of silver on a penny in the same way or would it require diff chemicals?
     
  7. Dec 22, 2009 #6

    chemisttree

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    Mirrors used to be made by plating silver onto glass using silver nitrate and formaldehyde. In the lab this is used in the "[URL [Broken] Test for aldehydes.[/url]
     
    Last edited by a moderator: May 4, 2017
  8. Dec 23, 2009 #7

    DrDu

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    silver is much more easy. However, you have to reduce the concentration of free silver ions considerably to obtain a lustrous cover. This can be achieved simply by rubbing a penny with a mixture of salt and silverchloride. Silverchloride is ill soluble and the free chloride ions reduce the concentration of silver even further. You can even prepare the chloride in situ by mixing some silvernitrate with rocksalt while wetting.
     
  9. Dec 23, 2009 #8

    Borek

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    This is slightly off topic, but you may find it amusing. Go to the page:

    http://www.chembuddy.com/?left=all&right=download

    scroll down and download diffusion simulation program. It nicely shows how structure of the electrodeposited substance depends on the deposition parameters. Basically it tells that the lower probability of the single ion reduction, the thicker and less spongy the deposit. This is in a way related to the low concentration givng nice, lustrous cover.
     
    Last edited by a moderator: Aug 13, 2013
  10. Dec 23, 2009 #9

    alxm

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    You'd probably have to silver-plate it before gold-plating it to get the best result.
     
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