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    Hey,

    There's question in my OCR textbook (p117, Q3 if anyone has it) and I'm not sure how they got to the final answer of
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    8.3 x 104 dm6 mol-2s-1


    Here's the question:

    The reaction between ozone and ethene has the following rate equation:
    rate = k[O3][C2H4]

    5.0 x 10-8 mol dm-3 of ozone was reacted with 1.0 x 10-8 mol dm-3 of ethene. The initial rate of this reaction was 1.0 x 10-12 mol dm-3

    Calculate k

    My method:

    k = 1.0 x 10-12 divided by 5.0 x 10-8 * 1.0 x 10-8

    Giving: 2000 dm3mol-1s-1
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    (Original post by Woody.)
    Hey,

    There's question in my OCR textbook (p117, Q3 if anyone has it) and I'm not sure how they got to the final answer of
    Spoiler:
    Show
    8.3 x 104 dm6 mol-2s-1


    Here's the question:

    The reaction between ozone and ethene has the following rate equation:
    rate = k[O3][C2H4]

    5.0 x 10-8 mol dm-3 of ozone was reacted with 1.0 x 10-8 mol dm-3 of ethene. The initial rate of this reaction was 1.0 x 10-12 mol dm-3

    Calculate k

    My method:

    k = 1.0 x 10-12 divided by 5.0 x 10-8 * 1.0 x 10-8

    Giving: 2000 dm3mol-1s-1
    your unit of the rate constant is correct. I mean based on the rate equation you are given, the unit of the rate constant given in the actual answer is already wrong. unit of rate is dm-3mol1s-1
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    (Original post by shengoc)
    your unit of the rate constant is correct. I mean based on the rate equation you are given, the unit of the rate constant given in the actual answer is already wrong. unit of rate is dm-3mol1s-1
    it is mol dm-3 s-1 in the book,

    although that has to be a major typo?? it is 2000 dm3 mol-1 s-1???
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    I also got 2000dm^3 mol^-1 s^-1
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    (Original post by LearningMath)
    I also got 2000dm^3 mol^-1 s^-1
    good times, i have found SOOOO many typos in this damn book :p:
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    (Original post by JordanCarroll)
    it is mol dm-3 s-1 in the book,

    although that has to be a major typo?? it is 2000 dm3 mol-1 s-1???
    I can't be bothered with the values, but based on the wrong unit the book gives, it is most likely the values are obtained wrongly, hence should be wrong as well.
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    yeh it sounds like a typo, you've worked it out right
 
 
 
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