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A student-made galvanic cell is proposed for temperature measurements of cell potential. This cell can be easily constructed by students, the materials needed are readily available and nontoxic, and the solution applied is in an attractive color. For this cell, the potential values are excellently reproducible at each temperature, and the potential–temperature coefficient is well measurable. This experiment illustrates the determination of thermodynamic properties of a cell reaction, such as changes in entropy, enthalpy, and Gibbs energy through measurements of cell potential as a function of temperature. Students are led to understand the significance of those quantities. They also get to know the role of a supporting electrolyte in the electrochemical system.

A previous study of prospective teachers found that students from different countries and different levels of electrochemistry hold common misconceptions, indicating that concepts were presented to them poorly. It also identified new misconceptions by considering electrochemical concepts such as chemical equilibrium, electrochemical equilibrium, and the instrumental requirements for the measurement of cell potential, which had been ignored in the literature. This paper reports how the prospective teachers' scientifically incorrect ideas were used to form assertion-reason-type questions and how these questions were used to identify previously unreported conceptual difficulties related to these ignored concepts. The origins of the learning difficulties were attributed to lack of electrochemical conceptual knowledge and to insufficient explanation of the concepts in the textbooks. The results of this study were consistent with the constructivist model of learning, which suggests that students construct new k...

This demonstration illustrates the importance of the role played by ion diffusion in determining the magnitude of the emf of a primary cell.