# Density, Accuracy, Precision And Graphing

1101 WordsNov 19, 20135 Pages
Experiment Density, Accuracy, Precision And Graphing OBJECTIVES 1. The determination of the density of water 2. A comparison of the accuracy and precision of a graduated cylinder and a pipet EXPERIMENTAL MATERIALS Part A A 50mL graduated cylinder A balance 50.0mL deionized water A rubber policeman Part B A 100mL beaker A 50mL graduated cylinder A volumetric pipet 120.0mL deionized water A thermometer A rubber policeman EXPERIMENTAL METHODS Part A: Density of water 1. An empty, dry 50mL graduated cylinder was obtained. 2. The mass of graduated cylinder with using a balance. 3. 10.0mL of deionized water was added to the 50mL graduated…show more content…
As it is showed in the table, each samples of water has the different density of water. However, those results are expected because the each values of the mass and volume of water are different. Also, the slope of the graph is defined as density of water. Therefore, the average of those results are showed in the graph (y=0.9833x). Part B: Accuracy and Precision Accuracy is determined by how close a measurement comes to an existing. In this experiment, it can be observed that which one is more accurate with the comparison of the graduated cylinder and the volumetric pipet. As a result, the volumetric pipet is more accurate than the graduated cylinder because the percentage error of the average density measurement of using volumetric pipet is lower than using the graduated cylinder. Precision is how close a measurement comes to another measurement. Precision is determined by a statistical method called a standard deviation. Standard deviation is how much, on average, measurements differ from each other. High standard deviations indicate low precision, low standard deviations indicate high precision. Mathematically the average deviation is not as significant as the standard deviation. However, in this experiment, average deviation is a measure of the precision of the measurement. As a result, the volumetric pipet is more precise than the graduated cylinder because the average