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# How to calculate Percentage uncertainty?? Watch

1. 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
2. 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%
3. yarghan
4. (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.
5. (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.
6. Yes you do. (Sorry for re-awaking a 4 years old comment and 6 years old post)
7. (Original post by Ahmed Alfarra)
Yes you do. (Sorry for re-awaking a 4 years old comment and 6 years old post)
Thank you for this. (sorry for re-surfacing an 8 year old post and 1 year old comment)
8. so the equation is going to be

(0.06 / 25) x 100 = 0.24%

(0.05 / 23.7) x 2 x 100 = 41%

(sorry for re-surfacing an 8 year old post and 1 week old comment)

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