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VidNuT 2 - acid-base

“Acids and bases” stumbling blocks for teachers and students
Acid-base reactions are a central topic in chemistry class. They are examples of chemical reactions that take place according to the donor-acceptor principle.

The Arrhenius acid-base concept is often taught at the start. This is considered easy to understand, but has limited explanatory power. That is why the much more viable Brønsted-Lowry concept is then introduced. Students are therefore required to change concepts, which, however, often cannot be fully implemented. This is due to mixed concepts as well as linguistically and symbolically unclear representations in teaching media, which teachers often adopt without reflection. However, the mixed concepts are not suitable for explaining acid-base reactions in a technically appropriate manner, which repeatedly plunges learners into conflicts of understanding.

Chemistry students also bring such mixed concepts into their studies. Even after several semesters, you often still mix parts of the two concepts. The conceptual confusion is sometimes so deep that the students are hardly able to explain simple acid-base reactions in a technically appropriate manner.

Learning opportunities in which students can recognize and reflect on inappropriate concepts in order to initiate a concept change are therefore of great importance. Only on this basis can a professional lesson perception be developed, which is the basis for successful chemistry lessons.


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VidNuT Designer:  Moritz Meier

VidNuT Expert:  Anja Lembens

Institution: Austrian Competence Center for Chemistry Didactics (Austria Educational Competence Center Chemistry; AECC Chemistry)
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