Corrected peak area. A micellar electrokinetic chromatography method for phthalazine and its metabolite 1-1- phthalazinone yielded the following repeatability for six replicate injections of a 50 μM 50 μM phthalazinone standard.

a. What is the difference between repeatability and reproducibility?
b. Determine the relative standard deviation for migration time and for peak area.
c. Calculate the corrected peak area, which is peak area divided by migration time, for each injection. What is the relative standard deviation of the corrected peak area? Why is it different than the peak area value determined in (b)?

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Injection number 11 22 33 44 55 Migration time (min) 3.9463.046 3.9213.921 3.9003.900 3.9323.932 3.9153.915 3.8813.881 Peak area (arbitrary units) 89478 947 9 1249 124 88348 834 9 2509 250 90579 057 8.9868 986