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    How do you do this? I've missed so much Chemistry, and I'm asked to do this in my coursework. I have no idea what I'm doing

    Thanks
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    You can't just make one up theoretically - the rate equation needs to be derived from the experimental data....
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    (Original post by Organ)
    You can't just make one up theoretically - the rate equation needs to be derived from the experimental data....
    What data do I need? I have it... I've done graphs and stuff :confused:
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    (Original post by Failed123)
    How do you do this? I've missed so much Chemistry, and I'm asked to do this in my coursework. I have no idea what I'm doing

    Thanks
    First, what is the experiment??
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    (Original post by yousif92)
    First, what is the experiment??
    It's the Iodine clock one, where you vary the concentrations of the Potassium iodide and the peroxodisulphate.
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    oh right. So did you take some of the reaction mix at particular times and titrate?
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    I expect that from the graphs you have drawn you are able to deduce what order each reaction is?
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    (Original post by yousif92)
    oh right. So did you take some of the reaction mix at particular times and titrate?
    Yeah, I did one experiement where I varied the concentration of the Potassium Iodide and measured the time it took for the mixture to turn blue-black. I also did the same in a different experiment with the Peroxodisulphate... and then I did temperature, catalyst etc.

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    (Original post by Keckers)
    I expect that from the graphs you have drawn you are able to deduce what order each reaction is?
    Yeah, the first ones are first order... with the concentration.
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    (Original post by Failed123)
    Yeah, the first ones are first order... with the concentration.
    Ok, so what equations do you know that tie the order of the reaction with the rate?
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    (Original post by Keckers)
    Ok, so what equations do you know that tie the order of the reaction with the rate?
    I don't know, I'm only basing this on the line of my graph :confused:


    I fail...
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    rate=k[A]x[B]y

    where k is the rate constant (k=Ae-Ea/RT)

    If the reactant is first order, the graph of concentration vs rate will be a directly proportional line, if zero order it'll be flat, if greater than 2nd order it'll be a curve.
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    Right pal, if you could stick up a plan of your experiment and explain step by step what was carried out, then we could help. But based upon what we know, you have a known conc of [KI]. Im assuming that you are reacting it to get some sort of substitution so you can get your I2 (blue/black). You are measuring the time for the reaction to complete. So from this, if you draw a graph of conc on the y axis and time on the x, then you can determine its order... But you are going to need to expand a little man...
 
 
 
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