unlabelled dichromates...

Discussion in 'Alternative Processes' started by Goza, Sep 18, 2008.

  1. Goza

    Goza Member

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    i've got 2 bottles...

    both unlabelled...

    one's potassium dichromate,
    one's ammonium dichromate,

    one's pinkish
    one's orange-ish

    which one's pink?
    which one's orange?
     
  2. Akki14

    Akki14 Member

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    I know my potassium dichromate is bright neon orange like unnatural koolaid... never seen ammonium dichromate.
     
  3. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    My potassium dichromate is bright orange.
     
  4. nze

    nze Member

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    Try to mix them with alcool or acetone, the one who precipitate is Potassium one.
    Or you can just add them to water Potassium saturate @9-10%
    So if you can add more it is ammonium if not it is potassium
    I 've got both and they are just similar in color.
     
  5. Goza

    Goza Member

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    that's good stuff. thanks guys.
     
  6. Katharine Thayer

    Katharine Thayer Member

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    Hi, I seem to have noticed this a little late. Are you talking about mixed solutions, or dry crystals?
     
  7. Goza

    Goza Member

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    dry crystals
     
  8. Katharine Thayer

    Katharine Thayer Member

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    Okay, then I'd second Chris's suggestion: mix some of one of them and if you can mix it to more than (I'd say 13% to be sure, because the amount needed for saturation depends on the temperature) then that's the ammonium, but if adding more than the 13% just results in crystals settling out that can't be incorporated into the solution, then that's the potassium.

    But I'm surprised they're different colors. I've only used potassium dichromate once (I'm an ammonium dichromate gal) but I don't remember the crystals being more pink than the ammonium dichromate. But that's just an idle comment, if you're sure that what you have is ammonium and potassium dichromate. Good luck,
    Katharine
     
  9. Goza

    Goza Member

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    Katharine,

    on the colors...

    they are pretty identical. The difference is pretty slight and only when I put them next to each other.