CHEM 212 Lecture Notes - Lecture 3: Propagation Of Uncertainty, Observational Error, Analyte
14 Sep 2016
School
Department
Course
Professor
Document Summary
Combo of tool and measurement you are trying to make. Precision balance and microanalytical balance weight. extra sig gs could be. How to select the right tool to make a measurement: Depends on the tolerance for uncertainty in the measurement. Balance used to weigh samples has an uncertainty of +-0. 02g. The same balance used to weigh a 0. 05g sample gives an uncertainty of 40% in sample. Steps following make an impact on how many sig gs you need too, because later the of no use because you have other limiting steps. Cylinders, beakers and asks ve only approximate values, thus, not for accurate. Use water of know t and know v and do three or four times to get an average. We will use the pipet for whole term. Replicate analysis needed because uncertainty in every measurement. Depends on how close the three measurements are together. If answers scattered, another measurement needed to get better average.
