Questions On Uncertainty Information On The Measuring Variables

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Uncertainty Information While measuring variables, uncertainty arose to accompany the values recorded, each of which depended on the measuring tool or documented uncertainty. A summary of the uncertainty information concerning the measured variables for the diffusivity testing of acetone and ethanol is included in Table 1. Table 1: Uncertainty Summary of Measured Variables Measured Variable Uncertainty Odds Reference Temperature ±1.0 °C 2.15-1 Online Instrument Documentation Pressure ±0.4 inHg 2.15-1 Online Instrument Documentation Mass ±0.0002 g 2.15-1 Online Instrument Documentation Height ±0.05 cm 2.15-1 Half Least Count Radius ±0.05 cm 2.15-1 Half Least Count Time ±0.5 min 2.15-1 Estimate In order to translate these…show more content…
For all of the tests conducted, the same apparatus was used, and the sample materials in the system were not altered between any of the tests. Seeing as the same apparatus was used for all tests, the inner chamber diameter of 2 inches remained constant for all tests. Additionally, the apparatus was purged with nitrogen immediately before the start of each trial to ensure that diffusion did not begin before the start of the timer. The information that was recorded for each test included the elapsed time, the weight of the condenser both before and after collecting the vapors, and the distance from the point of collection to the gas-liquid interface. In addition, the room temperature and pressure was recorded each day due to the role of these measurements in calculating the predicted values. For the testing of acetone, data was gathered at half hour intervals ranging from 30 minutes to 90 minutes. During these trials, the room temperature was recorded at 22.5℃ and the room pressure was 29.18 inches Hg. Raw data for the transient diffusion trials of acetone can be found in Table 2: Table 2: Experimental Results for the Transient Diffusion of Acetone Time Elapsed (min) Distance from Interface (cm) Empty Condenser Weight (g) Final Condenser Weight (g) 30 11.55 15.2772 15.2945 17.95 15.2635 15.2766 24.35 15.2712 15.2790 30.75
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