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galvanic cellZoomA-Z

Subject - General Chemistry, Physical Chemistry, Electrochemistry

The galvanic cell, an electric cell or galvanic element, is named after the Italian physician and naturalist L. Galvani. The galvanic cell refers to a set of electrodes which provide electrical energy by electrochemical reactions. The electrodes (positive elektrode = anode, negative electrode = cathode) are separated by a liquid, paste-like or ion-transporting electrolyte. Each electrode has a characteristic electrochemical potential. During the reaction one electrode reacts by giving up electrons (anodic oxidation) while the other takes up electrons (cationic reduction). If both electrodes are connected by an electrical conductor (wire), an electrical current flows between them because of the potential gradient (Abb. 1) .

Fig.1
Daniell element

Example of a galvanic cell.

Based on their function, galvanic cells are divided into primary elements (disposablebatteries) and secondary elements (rechargable batteries). Primary elements are constructed in such a way that the chemical compounds which are transformed during the process cannot be regenerated. In secondary elements, regeneration is achieved by applying an electrical current which reverses the chemical reactions that occur during their use.