High School Students’ Learning Difficulties in Brønsted-Lowry Acid-Base Theory

The definitions of acid and based had changed several times in one hundred years. Nowadays, many students need to learn two different acid-base theories during high schools: Arrhenius theory and Brønsted-Lowry theory. The purpose of this study was to understand high school students’ learning difficulties in learning Brønsted-Lowry theory, especially focusing on the transfer from Arrhenius definition to Brønsted-Lowry definition. Data were gathered using diagnostic assessment. There are 65 items in the assessment, including the concepts of conjugate acid-base pair, Brønsted-Lowry definition, amphoterism, acid-base equilibrium in aqueous solution, and buffers. The instrument was administered to 117 students of 11th grade who had learned Arrhenius theory only, and 188 students of 12th grade who had learned both Arrhenius theory and Brønsted-Lowry theory. The result shows that even students have learned Brønsted-Lowry theory, they do not completely transfer their acid-base paradigm from Arrhenius to Brønsted-Lowry. Instead. They preferred to combine these two theories and tried to use the compromised ideas in new situations. Students could understand Brønsted-Lowry definition which is about donating and accepting of protons, but they could not really catch the meaning of relative strengths of acids and bases. To avoid mistakes, they chose to solve problems by Arrhenius theory which they have already known well. In other words, when students are unfamiliar to used Brønsted-Lowry definition to think and solve problems in new situations, they may have difficulties in learning other related concepts, such as conjugate acid-base pair, amphoterism, acid-base equilibrium in aqueous solution, and buffers.

Science, Acids and Bases, New Thinking

Science, Mathematics and Technology Learning

Paper Presentation in a Themed Session

  • Huei Lee
    • Professor, Department of Education and Human Potential Development, National Dong Hwa University, Taiwan Taiwan
  • Hung Jen Yeh
    • Teacher, Zhong Zheng Senior High School, Taiwan Taiwan