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    I don't understand why the rate of reaction is 3.125 which it says on the mark scheme. The rate of reaction is calculated by finding the gradient and I did this for four to eight minutes as can be seen in the first photograph. My working is incorrect as the change in y is 7.5. But 7.5/4 = 1.875 not 3.125. Any help would be appreciated. Thanks in advance.
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    (Original post by Wolfram Alpha)
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    I don't understand why the rate of reaction is 3.125 which it says on the mark scheme. The rate of reaction is calculated by finding the gradient and I did this for four to eight minutes as can be seen in the first photograph. My working is incorrect as the change in y is 7.5. But 7.5/4 = 1.875 not 3.125. Any help would be appreciated. Thanks in advance.
    use a tangent bruv, it should tell ya where you got to measure the rate of reaction, is it inital rate of reaction ?
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    (Original post by money-for-all)
    use a tangent bruv, it should tell ya where you got to measure the rate of reaction, is it inital rate of reaction ?
    The question asks to calculate the rate of reaction from 4-8 minutes. I've never used tangents before in such questions...
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    (Original post by Wolfram Alpha)
    The question asks to calculate the rate of reaction from 4-8 minutes. I've never used tangents before in such questions...
    well, now is the time to start using them lad.
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    (Original post by money-for-all)
    well, now is the time to start using them lad.
    No, the question asks for the average, which can get by drawing a line through two points.
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    (Original post by Wolfram Alpha)
    The question asks to calculate the rate of reaction from 4-8 minutes. I've never used tangents before in such questions...
    You are asked to compare the rate for the first four minutes with the rate from 4-8

    There seems to be an error by the teacher. Point it out politely.

    Ignore the comment about tangents - your method is correct for average rate.
 
 
 
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