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Technical data

Connection of Daniell cells in series and parallel with Cobra SMARTsense

Article no: P7400569

Principle

A galvanic cell (Daniell cell) consists of two half-cells, in this case a copper sulfate solution with a copper electrode and a zinc sulfate solution with a zinc electrode. The zinc electrode decomposes while releasing electrons, whereas the copper electrode accepts electrons. Generally, only a small amount of current or voltage can be generated with a single galvanic cell.

Connecting several galvanic cells, e.g., Daniell cells, in series increases the electrical voltage. The increased voltage corresponds to the sum of the voltages of the individual cells. In a parallel connection, no increase in voltage occurs.

Tasks

Three Daniell cells are set up.
First two, then all three cells are connected in series, and the total voltage of the circuit is measured.
Two of the Daniell cells are connected in parallel, and the measured voltage is compared with the values from the series connection.

Learning objectives

In this experiment, students learn how to increase the efficiency of a galvanic cell by connecting them in series. The aim is to understand the relationship between the number of galvanic cells connected in series and the resulting voltage, as well as to recognize the differences compared to a parallel connection.

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.

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