For TESTING the electrical conductivity (ELC) of solids and liquids
a battery (9 V), a battery clip, a LED (5 V), a pin and a blister with water samples are needed.
Calcium and the carbon of a pencil lead close the electric circle: The LED shows bright light (photo).
Testing the ELC of water samples:
High ELC for salt solutions.
In order to MEASURE the current passing through water samples a digital multimeter is used.
First publication: 2002 Last modification: 11.04.2014