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Technical data

The Volta element with Cobra SMARTsense

Article no: P7400769

Principle

The first galvanic cell was described in 1799 by the Italian physicist Alessandro Count Volta. This so-called Voltaic cell, or Volta’s cell, is also a copper-zinc element. In contrast to the later developed Daniell cell, in the Voltaic cell both metal electrodes are placed together in one electrolyte solution of diluted sulfuric acid.

Thanks to its comparatively simple design, many of these cells can be connected in series in a space-saving way. These batteries, known as Voltaic piles, consisting of several Voltaic cells, were used to generate high voltages.

Tasks

The students set up two Voltaic cells. The voltage of a single cell and the voltage after series connection are measured.
The electrodes are short-circuited, and the hydrogen evolution as well as its influence on the cell voltage are investigated.

Learning objectives

Through this experiment, students deepen their knowledge in the field of electrochemistry and get to know another galvanic cell, the Voltaic cell. They analyze the electrochemical reactions at zinc and copper electrodes and examine the conditions under which hydrogen evolution occurs in a short-circuit. In addition, they record the influence of this reaction on the cell voltage.

Benefits

The experiment is part of a complete set covering all major curricular topics in electrochemistry.
Fast and simple experiment preparation (instructions and risk assessment available).
Increased student motivation through the use of the intuitive measureAPP (freely available).
Minimal preparation time: experimental literature for students and teachers available.
Easy teaching and efficient learning when using the interactive experimental literature.