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-   -   Iodine clock reaction with S2O3 ion (https://www.askmehelpdesk.com/showthread.php?t=110191)

  • Jul 15, 2007, 02:47 PM
    Olya315
    Iodine clock reaction with S2O3 ion
    In the iodine clock reaction with S2O3 ion I have found that one of the exponents in the reaction rate is 1.55. Can I round it to 2? Or shoud I write it as a fruction 3/2?

    I know that reaction rate can be a fraction. But it is a fraction in this case?

    Thank you! :)
  • May 8, 2009, 03:19 PM
    mirna sherry

    For sure it can be 1.55 you must leave it as it is.
  • May 8, 2009, 03:28 PM
    mirna sherry

    Thank you but iodine doesn't react with oxygen
  • May 8, 2009, 05:14 PM
    Perito

    This is in the wrong thread. Here is the original thread.

    https://www.askmehelpdesk.com/chemis...rs-351397.html

    Iodine certainly won't react with oxygen, but will it react with iodide? It certainly doesn't do it very often, but it can happen (the Winkler test requires a Manganese catalyst). Oxygen is a sufficiently strong oxidizer.

    Winkler test for dissolved oxygen - Wikipedia, the free encyclopedia

    Time-resolved reaction of oxygen(1.DELTA.) with iodide in aqueous solution - The Journal of Physical Chemistry (ACS Publications)

    E = - 0.54 volts

    E = 1.23 V

    ΔE = +.69 volts

    You can see that the electrochemical potential is there (which says nothing about kinetics). In addition, it only takes a tiny amount of iodine to turn starch blue. The last thing is that it's the only thing I can think of that's present that could oxidize iodide to iodine. Iodine has to be present or the starch wouldn't turn blue. I'm open to other suggestions.

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