BULLETIN FOR THE HISTORY OF CHEMISTRY
Volume 50, 2025
Jensen, William B.; Kugel, Roger W.; Pinhas, Allan R., “Some Unusual Voltaic Cells,”Bull. Hist. Chem., 2025, 50, 119-126.
https://doi.org/10.70359/bhc2025v050p119
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Abstract/Description: After first reviewing the treatment of the Nernst equation found in introductory and physical chemistry textbooks, this paper explores the older chemical literature in search of examples of unusual voltaic cells that teachers of these subjects can use to enrich their coverage of electrochemistry. The unusual cells covered in this paper include: allotrope (or transition) cells in which the electrodes are two allotropes of the same element; gravitational cells in which the anode and cathode are held at different potential positions in a gravitational field; and strain cells, in which the two electrodes are of identical metals, but in one of them the metal atoms are strained. In all of these unusual cells, there is a free energy difference between the metal atoms of the two electrodes due to: different metal phases; different gravitational potentials; or different mechanical strains on the metal atoms. In principle, these free energy differences should show up in the cell potentials, and thus they can be measured electrochemically in a single-compartment voltaic cell. However, the predicted electrical potentials are all in the microvolt range, and therefore are difficult to measure reliably.