Practical investigations
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Hi, I'm not sure about calculating % error. I know how to do it, but I'm not sure which measurments I need to find the % error of. I am investigating activation energy. I used temperatures from 25 C to 50 C, with 3 repeats for each, and then averaged the results. In order to calculate the percentage error, do I need to find the % error for each repeat and then total them to get the total error for the average for all 6 temperatures, or do I just find the % error of the lowest temp I measured out of all them (24 C), then multiply that by 3 (for each repeat) and use that as the % error for each of my averages? Or is it neither?!
Ulex replies
You could proceed along the lines you suggest, but what really matters is the extent of the error in the final result. I suggest you plot all three repeats for each temperature and then draw two different straight lines, using the maximum possible gradient and the minimum possible gradient. Calculate two values for the activation energy - the difference between the two is your error from which the % error can be calculated.
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updated: 12 February 2007
