How to Use Lemon to Generate Electricity? - Lemon Battery

Have you ever thought that without electricity what our world will look like? But this is never going to happen because we have the LEMON BATTERY. Just a joke. This is a cool science experiment to do at school. When the LED glows, most of the kids will ask why. This experiment teaches kids how power is generated and some basic concepts of physics and chemistry.

Ages: 5+            Est. Time: < 20 mins

 Safety 

1. Adult supervision.
2. Do not eat the lemon after this experiment.

 Materials list 

• Lemon
• Pieces of Copper (or copper coin)
• Pieces of Zinc (or galvanized nail)
• LED light
• Copper wires
• There are fruit battery kits available on Amazon.

 Instruction 

Step 1/3 – Softly squeeze the lemon to make it slightly softer. Insert a piece of copper and a piece of Zinc into each four lemons. (You can use a knife to open a small hole in the lemon making it easy to insert in.)

Step 2/3 – Connect the lemons in order of copper-zinc with wires.

Step 3/3 – Connect the copper end to the positive electrode of the LED light while the zinc end to the negative electrode. Then you get your Lemon Battery.

 Troubleshooting 

Why the LED is not on?

– Make sure If your wires are completely connected.

  Make sure your lemon is fresh enough so you have the maximum amount of chemical substance to power your LED.

 Make sure the wire is connected in the copper-zinc order. The copper piece is the positive electrode, and the Zinc piece is the negative pole. Like the battery, they need to be connected to the positive and negative pole. The LED needs to be connected in the right way to light. 

 Scientific description 

The principle behind this experiment is that copper, zinc, lemon, and wire form a battery. The chemical reactivity of copper and zinc is different. Zinc is more active than copper. When zinc is inserted in the lemon, it will react with the acid in lemon juice. Zinc loses electrons and forms zn2+ ions and the electrons lost by zinc pass along the wire. Copper, the H+ in the juice gets electrons at the copper end to form hydrogen so that the electrons flow in the wire to form a current. A lemon-copper-zinc battery generates a voltage of about 0.9-1V, and the voltage becomes larger when more lemons are connected to the closed-loop. There are three necessary conditions for the formation of the lemon battery:

1. The electrode material is composed of two metals with different chemical activities, like copper and zinc in this experiment.

2. The electrolytes (the lemon juice in this experiment).

3. A closed loop.

 Extensions 

Lemon is an amazing material for many science experiments. We keep secret messages with lemon juice. 

We pop up the balloon with the lemon peel without touching the ballon.

Apart from the lemon, you can use almost any fruit, like apple, orange, potato... to do the battery experiment.

 Disposal 

Wash the copper and zinc pieces with water and discard lemons into the litter bin.