Prof Gilbert LECTURE 2 CHEM 1211 Fall 10 1 Transitions Measurements in Chemistry SI and metric units with appropriate exponential notation and prefixes Your job become familiar with the common units and prefixes in the text Precision repeatability of a measurement vs accuracy how close the result is to the true value Express the uncertainty in measurements using significant figures Case studies in measurement uncertainty 1 What is the density of a golf ball 2 How many sig fig s in these average value of 5 determinations of the concentration of dissolved oxygen in the Muddy River 7 4 6 8 7 1 6 9 7 2 N 5 Mean 7 0 8 Dimensional Analysis SAMPLE PROBLEM A biotech company in Cambridge MA manufactures one of the leading drugs against multiple sclerosis It is shipped frozen in bottles that each contains exactly 250 mg of the active ingredient to another company where the solutions in the bottles are thawed and diluted so that the concentration of the drug is 61 6 mg L This solution is used to fill 0 50 mL syringes which patients self inject IM once a week A standard prescription fill is one month four doses injections How many prescriptions can be filled from the contents of one of the frozen bottles
View Full Document
Unlocking...