Batteries contain a chemical called an electrolyte, which allows a chemical reaction to occur between the electrodes, which creates electricity. Lemon juice will act as an electrolyte.

You Will Need:

• a lemon
• a brass drawing pin or thumbtack
• a steel paper clip
• a torch bulb
• electrical wire

Directions:

1. Place a brass drawing pin or tack and a steel paper clip into opposite sides of a fresh lemon.
2. Connect a low-voltage torch bulb (less than 3 volts) by two pieces of electrical wire to make the circuit.
3. The torch bulb should light up.

What happened?

The juice of the lemon acts as an electrolyte, similar to the contents of a battery. By using two different types of metal, one the anode, the other the cathode, electrons flow through the electric wire, via the light bulb, from one metal to the other. This causes the bulb to light!

Bibliography

Parker, S. Simple Chemistry (London: Kingfisher, 1990).