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  1. #1

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    unlabelled dichromates...

    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. #2
    Akki14's Avatar
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    I know my potassium dichromate is bright neon orange like unnatural koolaid... never seen ammonium dichromate.
    ~Heather
    oooh shiny!
    http://www.stargazy.org/

  3. #3
    David A. Goldfarb's Avatar
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    My potassium dichromate is bright orange.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
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  4. #4
    nze
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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.
    Chris Nze
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  5. #5

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    that's good stuff. thanks guys.

  6. #6

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

  7. #7

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    dry crystals

  8. #8

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    Quote Originally Posted by Goza View Post
    dry crystals
    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. #9

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    Quote Originally Posted by Katharine Thayer View Post
    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
    Katharine,

    on the colors...

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



 

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