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How do you calculate the initial rate of reaction?

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    • Thread Starter

    I always think I understand it, but then as soon as I come across an exam question on calculating the initial rate of reaction, I get the wrong answer (by far).

    What I'm really confused by is when text books say 'draw a tangent' with no indication how far the tangent goes and where to read off!

    Also, do I subtract the Y axis reading from the top of the curve or from the top of the axis? Or just not subtract at all? And what about the x axis?

    The most confusing 2 marks 😳
    I would really appreciate any help ☺️

    The initial rate of a reaction is the instantaneous rate at the start of the reaction (i.e., when t = 0). The initial rate is equal to the negative of the slope of the curve of reactant concentration versus time at t = 0.

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Updated: June 5, 2016
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