Graphical Application to Assist Students Understand the Basic Concepts in Acid–Base Titrations

Abstract

During the 1960s, Edgar Dale published the concept that learners are likely to retain more information if they see and hear information rather than just listen. Therefore, many educational applications have been created for students to learn theoretical concepts through visuals and in an interactive manner. Microsoft (MS) Excel has been used in many of these applications due to ease of use and widespread applicability. The main objective of this research is to introduce an MS Excel application to study the theoretical concepts associated with acid–base titrations. This application allows the user to select the type of titration, Ka/Kb values where applicable, concentrations of the reagents, titration volume, commonly used indicators, and follow the variation in the titration curve. With the use of the application, students can clearly visualize the change in pH during the titration, buffer region, and the effect of reagent concentrations and Ka/Kb values on the titration curves. It further allows the user to determine the end point of the titration via a first derivative plot, observe the variation in fractional composition of the reactive species with pH, and identify the indicator best suited for the titration. The application was proven successful when used to teach the concepts of acid–base titrations to a group of high school students.