8.2x10 15 Accuracy and Precision Exercise A student uses 4 different instruments to measure 1ml of water. The density of water is approximately 1g/ml (it varies based on temperature) so 1ml of water should weigh 1g. 1. Complete the average mass and % error column in the chart. In your percent error calculations, use the average mass as your experimental value and 1g as your theoretical value. % error should be rounded to 2 decimal places. (8 points) Trial 1 Trial 2 Trial 3 Average % Error Mass of 1ml of 1.212 water measured with a "baby 1.254g 0.857g 1.524g beaker" Mass of 1ml of water measured with graduated cylinder Mass of 1ml of 0.958g 1.12g 0.915g water measured 0.998g 0.999g 0.999g with Micropipette #1 Mass of 1ml of water measured 1.251g 1.250g 1.251g with Micropipette #2 1. Comment on the relative accuracy/precision of each of the 4 instruments in the table below. yes or no will suffice) (8 points) Accurate? Precise?

8.2x10 15 Accuracy and Precision Exercise A student uses 4 different instruments to measure 1ml of water. The density of water is approximately 1g/ml (it varies based on temperature) so 1ml of water should weigh 1g. 1. Complete the average mass and % error column in the chart. In your percent error calculations, use the average mass as your experimental value and 1g as your theoretical value. % error should be rounded to 2 decimal places. (8 points) Trial 1 Trial 2 Trial 3 Average % Error Mass of 1ml of 1.212 water measured with a "baby 1.254g 0.857g 1.524g beaker" Mass of 1ml of water measured with graduated cylinder Mass of 1ml of 0.958g 1.12g 0.915g water measured 0.998g 0.999g 0.999g with Micropipette #1 Mass of 1ml of water measured 1.251g 1.250g 1.251g with Micropipette #2 1. Comment on the relative accuracy/precision of each of the 4 instruments in the table below. yes or no will suffice) (8 points) Accurate? Precise?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter8: Sampling, Standardization, And Calibration

Section: Chapter Questions

Problem 8.17QAP

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