Statistical Comparison of Data in the Analytical Laboratory

In this article, an experiment designed to provide students with an experience involving statistical treatment of data is described. Most courses that deal with quantitative analysis focus on methodology; students must learn how to perform specific types of analyses or students learn how to perform different procedures to analyze an identical unknown. Often overlooked, however, is the need to be able to justify the answer obtained through these experimental procedures. By teaching students statistical methods of comparison in the context of a laboratory experiment, they gain a better understanding of accuracy and precision. This experiment allows students to compare 11 different techniques for measuring specific volumes of water. Replicate measurements are taken for each technique and comparisons are made both within a data set and between different data sets. Through calculation of t-values, students are able to draw conclusions about the precision and accuracy of these various techniques. Furthermore, this experiment serves to provide instruction on proper use of different analytical glassware.