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How to calculate Percentage uncertainty??

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    Here are the questions:

    Calculate the percentage uncertainty associated with the volume of sodium carbonate which you have transferred using a pipette (uncertainty associated with reading a 25cm3 class B pipette is 0.06 cm3)

    Calculate the percentage uncertainty associated with your average titre (uncertainty associated with each reading of a 50cm3 class B burette is 0.05cm3) My average titre reading was 23.7
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    Percentage Uncertainty = (Absolute Uncertainty / Measured Value) x 100

    Therefore:

    % for pipette = (0.06 / 25) x 100 = 0.24%


    % for burette = (0.05 / 23.7) x 100 = 0.21%
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    yarghan
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    (Original post by Nirgilis)
    Percentage Uncertainty = (Absolute Uncertainty / Measured Value) x 100

    Therefore:

    % for pipette = (0.06 / 25) x 100 = 0.24%


    % for burette = (0.05 / 23.7) x 100 = 0.21%
    Do you not multiply the second one by two (assuming the calculation for average titre was made from two values)? Sorry for re-awakening a 2 year old thread.
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    (Original post by ERdoctor)
    Do you not multiply the second one by two (assuming the calculation for average titre was made from two values)? Sorry for re-awakening a 2 year old thread.
    yes, you do.

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Updated: July 3, 2012
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