Pluchino – Regents Chemistry Matter and Measurement – 02 Precision, Accuracy and Error Aim: How do we evaluate measurements and data in chemistry? Do Now: What is the difference between precision and accuracy? Precision: the ability to reproduce the same result again and again Accuracy: how close your measurements are to an accepted value Practice: Describe the location of the darts in terms of precision and accuracy. Error: the difference between your measurement and the accepted value % Error = measured – accepted x 100 accepted It is possible to have a negative (-) % error! Practice: Calculate the percent error. You measure the mass of a sample to be 4.55 g.
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This note was uploaded on 01/01/2012 for the course CHEM 101 taught by Professor Donahue during the Spring '11 term at Long Island U..