Science Experiments for Kids: Make a Lemon Clock

Observations

Ask Yourself:

• Why do you think we needed to use zinc and copper nails?
• Why is the clock lighting up?
• Why do we need to connect Lemon 1 and Lemon 2 to each other?
• How are the lemons like a battery when they are attached?
• What is it about the lemon that allows it to conduct electricity?
• What other foods do you think would conduct electricity?

What's Going On

When you put the zinc and copper in the lemon juice, it creates a chemical reaction that changes chemical energy into electrical energy. This change of energy is a voltaic reaction, which turns the lemons into a voltaic battery. The chemical reactions push the electrons that are being released from each metal through the copper wire and, because the metals are different, the electrons push harder in one direction. They move in a circular direction, going through the wires to the clock terminals and back to the lemon, making an electric current that may be powerful enough to power the clock. Once the lemon juice starts to dry up, the reaction will lessen, and you will need to change the "battery."

Extend the Learning

Try using different citrus fruits, orange juice, or soda to see how they work as voltaic batteries.