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Chemistry A level - Percentage uncertainty watch

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    How would you work out the percentage uncertainty of the volume of CO2 gas collected if a 250cm3 measuring cylinder is graduated every 2cm3 and 109.5cm3 of gas was collected? The measuring error 1cm3, and do I need to change the volume to dm3. Please help. Thanks
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    Cm3 to dm3 you divide by 1000
    Your uncertainty in the volume is +-1cm3, so your measrement should be 110+-1, or about 0.9%
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    (Original post by zara_ruby)
    How would you work out the percentage uncertainty of the volume of CO2 gas collected if a 250cm3 measuring cylinder is graduated every 2cm3 and 109.5cm3 of gas was collected? The measuring error 1cm3, and do I need to change the volume to dm3. Please help. Thanks
    You shouldn't need to change the volume to dm3 because all needed numerica values are in cm3. Just do +- 1 (half the smallest interval)/ 109.5 x 100 to get the percentage uncertainty
 
 
 
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