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    Hi,

    I was wondering if there are other ways of determining the rate of reaction between hydrogen peroxide and potassium iodide other than doing the clock method.

    Thank you
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    (Original post by supernovainthesky)
    Hi,

    I was wondering if there are other ways of determining the rate of reaction between hydrogen peroxide and potassium iodide other than doing the clock method.

    Thank you
    I suppose good thing about the iodine clock reaction is that it is easy to spot when an alternating reaction initiates or ends via change of colour.

    Perhaps alteration with use of transition metal redox reactions could yield you similar results? after all, different aqueous transition metal ions tend to have distinctive colours.
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    (Original post by supernovainthesky)
    Hi,

    I was wondering if there are other ways of determining the rate of reaction between hydrogen peroxide and potassium iodide other than doing the clock method.

    Thank you
    Check out the equation for the reaction:

    H2O2 + 2I- + 2H+ --> 2H2O + I2

    Now look for things you can monitor (follow) over the course of the reaction.

    Hydrogen ions are disappearing, so maybe pH
    In general ions are disappearing, so maybe conductivity
    Iodine is appearing, so maybe colorimetry.
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    (Original post by charco)
    Check out the equation for the reaction:

    H2O2 + 2I- + 2H+ --> 2H2O + I2

    Now look for things you can monitor (follow) over the course of the reaction.

    Hydrogen ions are disappearing, so maybe pH
    In general ions are disappearing, so maybe conductivity
    Iodine is appearing, so maybe colorimetry.
    If I used colorimetry, how would I detect the colour change in order to measure absorbance at different times?

    Thanks btw
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    (Original post by supernovainthesky)
    If I used colorimetry, how would I detect the colour change in order to measure absorbance at different times?

    Thanks btw
    You would use a colorimeter set to absorb in the complementary colour to blue and starch solution.

    As the iodine is produced the starch gets darker and the absorption gets greater.

    Reference solutions of known concentrations in iodine, standardised starch and a calibration curve graph etc.
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    (Original post by charco)
    You would use a colorimeter set to absorb in the complementary colour to blue and starch solution.

    As the iodine is produced the starch gets darker and the absorption gets greater.

    Reference solutions of known concentrations in iodine, standardised starch and a calibration curve graph etc.
    Thank you that helps a lot DDDDDDDDDDDDDD
 
 
 
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