Inquiry-Based Laboratories for Students to Investigate the Concepts of Acid–Base Titration, pK_a, Equivalence Points, and Molar Absorption Coefficients

Abstract

This research developed learning activities for students to explore and connect the concepts of acid–base titration, equivalence points, pK a, and molar absorption coefficients. Polyphenolic compounds consisting of p-coumaric acid (CMA), caffeic acid (CFA), and 3,4,5-trihydroxycinnamic acid (3,4,5-THCA) were selected as study models. The inquiry-based learning activities consisted of four phases, including in-classroom, prelaboratory discussion, in-laboratory work, and postlaboratory discussion. This research was conducted through a single group pretest–posttest design, and the learning activities were implemented with biochemistry undergraduate students. Data were collected using conceptual pretest and posttest, questionnaires, and laboratory reports. The paired-sample t test results showed that the mean posttest score (51.29 ± 10.46) was significantly higher than the mean pretest score (19.00 ± 5.90). The results implied that students had a better understanding of the concepts and the links between the concepts of acid–base titration, pK a, equivalence points, and molar absorption coefficients. These findings were supported by information from questionnaires and laboratory reports. The results showed that the students had moderately positive attitudes toward laboratory activities, the instructor, and the content. Overall, the results indicated that the laboratory activities embedded with the inquiry-based approach were effective, as they enhanced the students’ understanding of concepts and promoted students’ positive attitudes toward laboratory activities.

Metal Demon Conqueror Game: A New Digital Game-Based Learning Tool on Factors Affecting Enzyme Activity

“…We computed the student tallies from their responses and calculated the means of their scores, adopting our criteria for data analysis from previously conducted research. Thus, student attitudes were interpreted as negative (scores < 3.0), neutral (scores = 3.0), slightly positive (scores of 3.1–3.5), moderately positive (scores of 3.6–4.5), and highly positive (scores of 4.6–5.0) . The percentages for each score on the Likert scale were calculated for each item (Figure and Tables S1–S4).…”

“…Thus, student attitudes were interpreted as negative (scores < 3.0), neutral (scores = 3.0), slightly positive (scores of 3.1−3.5), moderately positive (scores of 3.6−4.5), and highly positive (scores of 4.6−5.0). 43 The percentages for each score on the Likert scale were calculated for each item (Figure 6 and Tables S1−S4). A further analysis was performed to group the percentages of students who agreed (green) or strongly agreed (blue) with positive attitude items, those who disagreed (orange) or strongly disagreed (red) with negative attitude items, 44 and those who neither agreed nor disagreed (yellow) with moderate attitude items.…”

A Comprehensive Teaching Laboratory Program on Titration Analysis: Transition from Classic to Modern Approaches

“…In the food industry, it is employed to analyze the composition of food products, thereby guaranteeing their safety and quality. While titration is a familiar concept to high school students and chemistry enthusiasts alike, university students in lower-level analytical chemistry laboratory courses must not only master its basic operation but also demonstrate their understanding of advanced chemistry principles through experiments. , Consequently, when devising analytical chemistry laboratory courses, it is imperative to consider the varying levels of students and craft suitable experimental programs for them. Beyond traditional buret experiments, a plethora of intriguing experiments can be devised by coupling burets with other gadgets.…”

Prelaboratory Practice with a Titration Simulation Program for Carbonate Mixtures

“…The titration curve is an important tool for students to understand the principles underlying the titration process. , A titration curve simulation platform can provide a fast and convenient method of simulating titration curves with various parameters. Various platforms offer simulations of acid–base titrations, including those based on Spreadsheet, Excel, − LabVIEW, and Matlab .…”