How Does Lemon Juice Conduct Electricity and Light a Light Bulb?

A sliced lemon

Powering a light bulb with lemon juice is a common science experiment that can help students understand batteries and electricity. Lemons function as batteries and provide the energy to light a small bulb.

Creating the Battery

According to the California Science Center, to perform the trick a lemon battery is set up by inserting a zinc electrode into one side of a lemon and a copper electrode in the other side, then attaching an LED light to the two electrodes using copper wire. The California Science Center suggests using multiple lemons for more power.

Electrolytes

The California Energy Commission explains that this is a voltaic battery, meaning that the lemon battery makes electricity from chemical energy. The California Energy Commission states that this forms a battery because the acid in the lemon juice is an electrolyte, an electricity-conducting solution.

Lighting the Bulb

Electrons gather at one electrode, and the other electrode loses them, the California Energy Commission explains. The California Science Center explains that the resulting current, the flow of electrons, is electricity. It is that electricity that powers the light bulb.

References

• California Science Center: Lemon Light
• California Energy Commission: Science Projects -- Lemon Power