Aim: To check if potatoes can conduct electricity, and if so to observe which type of potato conducts electricity the best . Lastly identify which feature of the potato allows it to conduct electricity.
Hypothesis/ Prediction: We think potatoes will conduct electricity because potatoes have moisture, inside the moisture there is water and water conducts electricity.
Materials: 4x sticky tape straps, 1x knife, 2x zinc strip, 1x sweet potato, 2x copper strip, 2x jacket potato, 2x ped potato, 2 small cup, 1x potato powered clock connected with Red and Black wires (positive and negative), 1x connecting wire, 1x ruler, 100ml water, 1x pen and 1x camera (optional, for observations)
Method: S1- Connect 1x copper strip with 1x zinc using connecting wire.
S2- Secure with tape ( one piece for each strip).
S3- Insert copper strip into first potato and insert zinc strip into second potato.
S4- Connect the black (negative) wire from clock to zinc strip and secure with tape.
S5- Connect the red (positive) from clock to copper strip and secure with tape.
S6- Insert second copper strip into second potato, then insert second zinc stripninto first potato.
S7- Clean copper and zinc strip before repeating the experiment.
S8- Repeat steps 3 and 6 for red potatoes and sweet potatoes, explore whether the whole sweet potato can be used as a battery, if it needs to be halved or if the clock requires 2 sweet potatoes.
S9- Use knife and cut skin off the potato, test to see if it produces electricity by repeating steps 3&6. Do the same with the inside of the potato, only use fractions of the potato for the rest of the test do not just put the strips.
S10- Pour Water (the water substitutes as potato juice) into the 2 cups and repeat steps 3&6.
- Potatoes can produce electricity.
- We have made a clock work with the PJP.
- All the potatoes we have tested have worked.
- We have shown that you do not need two sweet potato, two jacket potatoes or two red potatoes to power a clock.
- Movement of the potato for the JP and RP effects the clock but the SP with no connecting wire does not get effected by movement.
- 1 SP, 1 JP and one SP do not need a connecting wire to work only the black and red clock wires.
|Red Potato||Sweet Potato||Jacket Potato||Poisonous JP|
|Does it produce electricityYes: 1 No: 0||Does it produce electricityYes: 1 No: 0||Does it produce electricityYes: 1 No: 0||Does it produce electricityYes: 1 No: 0|
|If so how1. 5mm2. 5mm
|Far does1. 5mm2. 5mm
|It need to1. 5mm2. 5mm
|Go in1. 5mm2. 5mm
|Total Combined Length for 1 and 2 of each potato|
|Individual Section Report: Potatoes wont power without juice, but the skin of a potato will. The juice of a potato works perfectly.|
Discussion: The juice of a potato acts as an electrolyte which creates a chemical reaction that produces electricity. The electricity that is created by this chemical reaction, can be used to power LED clocks, lights etc. In this experiment the zinc and copper are your cathodes and anodes. Once you have placed the wire in between the two potatoes there should be no connection between the copper and zinc electrodes, if there is there, only heat will be created.
The reason for this chemical reaction is flowing electrons moving from one potato to another. The electrolytes in the potatoes are used as a source of transportation for flowing copper and zinc ions moving from one potato to another. In the experiment the potato acts as a facilitator to the electro- chemical reaction, it is because of the phosphoric acid (H3PO4) inside of the potato that allows the electro- chemical reaction to occur.
Zinc is a reactive metal, which is why it reacts quickly with acid to liberate electrons. The acid’s active ingredient is positively charged hydrogen, which is why a transfer of electrons takes place between the zinc and acid. When this takes place the zinc (Zn0) is oxidized (Zn++ ), and the hydrogen is reduced to hydrogen gas. The reaction at the penny decreases the electrons from the copper and attaches them to the hydrogen ions in the phosphoric acid.
So to summarize what I have just said, there are three main things that occur to make a potato power something. The first is oxidation, this is where the zinc loses two of it electrons. The second is reduction, this is where the hydrogen atoms get two electrons from the zinc. The last is the potato acting as an electrolyte to complete the circuit, which is what we were talking about the paragraph above.
In our experiment, we also discovered that potatoes can produce electricity and that a chemical reaction allows the potato to do this. We also found out that as well as the juice of the potato, the skin can be used to create electricity too, you can see this happens in the result/observation of when you remove one metal strip from a potato, the LED clock turns off.
This experiment has been performed using a copper penny and a zinc nail in a potato to power an LED clock, which is what we have found when looking on the web for our discussion. But we did this experiment with a zinc and copper rod, as I had some from a kit I got last year.
Conclusion: In our experiment we decided that we would change a variable. We changed the potato that we tested, to see if only some types of potatoes can be used to power small gadgets. We also tested the individual parts of a potato. To see if it is only the potato itself that can produce electricity. From this we found out that it is mainly the juice, which acts as an electrolyte to produce electricity. The juice also contains phosphoric acid, which is a core factor that is needed when doing this experiment.
In this experiment we had very good resources and tools which made this experiment work very well, but we believe that we could of found a better way of representing/ using each individual part of the potato. For any further investigations I suggest that you should always have a camera on stan by because you never know what might happen. remembering not every single potato is the same.`