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Where do you buy pottasium iodine, not the kind that you eat

  1. Dec 20, 2008 #1
    I am trying to do the elphant's toothpaste experiment, exepct i can't fint where to but potasium iodine at! Alls that i can find on the web are pills of it to protect your thyroid.
  2. jcsd
  3. Dec 20, 2008 #2


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    Potassium iodine?
  4. Dec 20, 2008 #3


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    The Elephant’s toothpaste experiment works by decomposing Hydrogen Peroxide (H2O2), with the aid of a catalyst, which is mixed with some soap. When the H2O2 decomposes it produced Oxygen gas. All that Oxygen forming makes bubbles in the soap and expands to fill (and then over-flow) the container it is placed inside.

    Potassium Iodide is used, amongst other things, as a photography chemical.

    Although I have never done this myself so as to say for certain that it will work…
    Since the catalyst (in this case Potassium Iodide, KI) is not used up in the process of decomposing the H2O2, even the small amount of KI in those thyroid pills may work for your needs.

    There are alternative catalysts you may use to decompose H2O2. Manganese Dioxide (MnO2) will also work quite well. MnO2 is a pottery supply chemical and is also found inside dry cell batteries.

  5. Dec 21, 2008 #4


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    In case you didn't notice: it is potasium iodide vs potassium iodine.
  6. Dec 21, 2008 #5
    that video in the link uses a lot of KI. i tried this with 3%H2O2 and detergent and got diddlysquat with a small amount of colorless iodine tincture used (water, alcohol, KI and NH4I).

    try a google product search with "potassium iodide reagent"
  7. Dec 22, 2008 #6


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    Any transition metal will decompose peroxide. I've used ferric chloride. I'm sure a crushed up vitamin/mineral pill would do the trick as well. Try mashing up a chewable vitamin pill into a small volume of water and add it to the peroxide.
  8. Dec 23, 2008 #7


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    Yeah , just do not do it with peroxide that is 30 % and above , any type of contaminent is bad for peroxide here.
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