Can electricity swim?

When you tested for conductors, did you test any liquids? Try some now in this circuit.

You will need:

• 4.5 volt battery
• 2.5 volt bulb
• Bulb holder
• Switch
• 4 leads
• 2 iron nails
• Cardboard
• Clear sticky tape

You can use a variety of liquids, such as vinegar, water, oil, salty water, sugar dissolved in water, and soapy water. There ate many more you can try.


Arrange the experiment as the picture shows. The nails in this experiment are there to conduct the electricity into the liquid and out of the liquid. Substances that are doing this job are called electrodes.

First use tap water in the jar. Does the bulb light? Does anything happen in the jar? Does the liquid conduct electricity? Add some soap to the tap water. What happens?

Pure water (distilled water-this can be bought from a garage) makes an interesting investigation. Make sure your jar is very clean and dry before you put the pure water into it. What happens?


Make the pure water salty by adding a teaspoonful of salt. What do you notice now?

If you add a lot more sea salt, so much in fact that some is left undissolved at the bottom of the jar, what do you notice happening in the jar?

In all your experiments look carefully to see if anything happens near the electrodes.

Now try some other liquids and record your results in table like this.



In some cases, you may have seen bubbles of gas appear in the liquid near an electrode. Did you notice which terminal of the battery the electrode was connected to? Was it the same in all the experiments where bubbles of gas were seen? In other cases the colour of the liquid changed.

In these experiments the electrical energy has made a chemical change in the liquid. Liquids that conduct electric currents are known as electrolytes.