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Technical data

Electric voltage from a salt solution with Cobra SMARTsense with Cobra SMARTsense

Article no: P7400269

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Principle

If a copper and a zinc sheet are immersed in a salt solution, a DC voltage can be measured between these sheets. In this salt solution, the less noble metal (in this case zinc) gives off electrons to the more noble metal (in this case copper). The metals used act as so-called electrodes. In this experiment, students therefore learn how to generate a DC voltage in a salt solution using two electrodes and how this can be easily measured using the Cobra SMARTsense voltage sensor and the PHYWE measureAPP.

Tasks

Use two different salt solutions to test whether a direct electric voltage can be generated between a zinc and a copper electrode.
What is the magnitude of this voltage, and which physicochemical principles are responsible for its generation?

Learning objectives

Students should deepen their understanding of basic electrochemical processes. To illustrate these, the experiment explains how to generate a direct voltage in a salt solution using two electrodes. The concept of "voltage" is also explored in more detail.

Benefits

The experiment is part of a complete set that covers all important curricular topics in electrochemistry.
Quick and easy experiment preparation (experiment instructions and hazard assessment available).
Increased motivation among students through the use of the intuitive measureAPP (available free of charge).
Increase in media literacy.