Using Control Charts Early in the Quantitative Analysis Laboratory Curriculum

Statistical process control (SPC) is used in the chemical industry to monitor manufacturing and laboratory processes to ensure quality and compliance with regulatory requirements. Control charts are a key tool used in this monitoring. Industrial job postings desire experience with SPC. Most undergraduates entering the workforce have no exposure, let alone experience, with control charts. The few available literature examples of control charts in undergraduate chemistry education involve methods of instrumental analysis at the junior or senior level of an academic program. Educators may improve the student’s preparation for working in industrial and regulatory environments by incorporating components of SPC early in the curriculum. This work provides an example of how to introduce the concept and use of control charts earlier as part of the Quantitative Analysis Laboratory curriculum. The titration of vinegar to determine the weight percent of acetic acid, using the same sample for all students, serves as a platform for this introduction. Using a provided control chart generated from historical student data, students stated in a written laboratory report if their results were within control. The scored laboratory reports and questions on the written final exam assessed student learning and retention of how to use a control chart. Meeting the learning outcomes for the laboratory exercise required the student to report the correct weight percent of vinegar and state whether their result is within control. The learning outcomes on the written final exam were met when the student answered the questions correctly, stating the given result was out of control and suggesting correct experimental changes. The goal was to see 70% or more students meet the learning outcomes. Assessment showed that a simple titration experiment enables the introduction of how to use control charts during the Quantitative Analysis Laboratory curriculum.