Data Sheet

1mA
Set the meter (M5) to the 1mA scale and connect the jumper wires to it. Connect the
other ends of the jumper wires to the snap electrodes (red to copper) , and place them in a
cup of water.
Read the current on the meter, if it is zero then your water is relatively free of impurities.
Having impurities does not mean your water is unsafe to drink. You can try dissolving
salt in the water and see if the current changes.
If you have some distilled water, test it. It should have zero current.
Replace the water with fruit juices and see how they compare. Sour tasting juices like
lemon or grapefruit juice usually produce the most current.
Don’t drink any water or juice used in this project. Wash any juice off the electrodes.
Project 82
Water Impurity Detector
The water in some areas is slightly acidic
due to impurities in it. This may be strong
enough to produce a current by reacting
with the electrodes, similar to how a bat-
tery works. These impurities should be
safe to drink.
Some fruit juices are more acidic and will
produce a higher current.
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