A Quantitative Examination of Multiple Methods for Standardizing a Dilute Hydrochloric Acid Solution in an Undergraduate Chemistry Laboratory

The objective of the project was to compare the different published methods for standardizing dilute hydrochloric acid solutions. To date there are no known studies that have examined the possible methods of standardizing dilute HCl solutions for accuracy and precision when performed by undergraduate students. There are three different suitable bases available for the process and multiple indicator choices. This article attempts to identify the most accurate method(s) for use in the undergraduate laboratory. Students were given an "unknown" solution of dilute HCl and assigned to standardize it by eight methods (32 titrations), reporting both their experimental results and preference for the different indicator–base combinations. The results from a small sample of students indicate that there are some accuracy differences between possible methods.