For this project we designed and created two different batteries, and compared them to each other. Our first battery was a “Electric dough Battery” this was normal dough, only mixed with lemon juice and salt. We thought the lemon juice and salt would create enough energy, and have enough electrolytes to light and LED bulb. Although the battery did not light an LED, there where in theory some energy transfers occurring from out electric dough.The electrons moved from the anode to the cathode, the oxidation reaction occurs in the anode strip and the reduction took place in the cathode strip which helped the electricity flow. This reaction occurs when there was acid, salt or electrolytes with the metals to create a reaction. We also created a soda battery. This was where we put conductress inside soda, in hopes that the electrolytes in the soda would have a strong enough current to light and LED bulb. This batteries also did not light and LED but there were still energy transfers occurring. The process that this battery uses to create electricity is very similar to the lemon battery, in the way the the electrons move through the anode to the cathode, and an oxidation reaction occurs in the anode strip. The energy transfers from the reaction occurring in the soda to the copper and zinc, then through the alligator clips into the voltmeter or LED bulb.
Presentation
Scientific Reasoning and Concepts
For our second round of experimenting we changed many aspects of our project in hopes that it would make our battery more efficient and eventually light an LED. For our electric dough we thought that adding more salt and lemon would increase the efficiency of the dough. We thought that adding more salt (NaCl) would increase the amount of ions(Na+ and Cl-) inside the dough which would cause the dough to be able to conduct more current. Adding salt increases more current in out battery. This meant that adding salt to the play dough did increase because the dissolved salt increase the amount of ions in our dough. We also thought that adding more lemon juice separately from the salt would increase the productivity of our battery. We did this because lemon juice contains citric acid (C6H8O7), and when citric acid dissolves in water hydrogen dissociates from the rest of the acid to form the ions H+ and C6H7O7- these ions allow more current to be able to run through the dough which makes it a more efficient battery. This did improve the efficiency of our battery making the voltage go from .64 volts, to .8 volts. This proves our idea that adding mare lemon juice into the dough would increase the efficiency of our battery by increasing the amount of ions and electrolytes in the dough. Then we thought that combining more salt and lemon juice in the dough would cause the battery to become more efficient. We thought that the salt ions and citric acid ions would create a lot of current running in the battery which would cause an increase in voltage. Unfortunately this made out electric play dough less significant than before. This was because the salt ions where reacting with citric acid ions to cause a double displacement reaction, which decreased the amount of ions in our solution, which in turn decreased the efficiency in out dough. The ions in the salt Na+ and Cl- where combining with to ions in the citric acid H+ and C6H7O7- to form HCL and NaC6H7O7. We also thought that adding both lemon juice and salt to the Gatorade battery would make it more efficient. Like the electric play dough, when we added the salt and lemon juice it made the battery less efficient for the same reasons that it made the electric play dough less efficient. We also thought that changing out zinc with magnesium would cause the battery to be more efficient. When we did this it caused tremendous improvement in both of our batteries. The reason the magnesium worked better than the zinc is because the standard reduction of magnesium is much greater than the reduction of zinc. Zinc has a standard reduction potential at 25*C of -0.763v and Magnesium one of -2.37.
Charge Electric Playdough (1st Trial) Soda Battery (1st Trial) Salt Playdough Lemon Juice Playdough Gatorade
Copper/zinc (Volts) 0.64 0.42 0.8 0.8 0.91
Copper & Magnesium (Volts) N/A N/A 1.6 1.5 1.78
Did it Light LED NO NO NO NO NO
Our energy traveled from the chemical energy that occurred from the citric acid reacting with the magnesium, then the energy produced in that reaction traveled through the copper wires to either the voltmeter or to the LED. In theory if our first battery should have been more efficient, because the copper has a half reaction of .337v and zinc has a half reaction of -.763 when subtracting the anode from the cathode you should get I.337-(-.763)I= 1.1v. This means our batteries where losing energy somewhere along the lines. This energy could have been lost due to heat energy or human error. Also when we re-tested our batteries with magnesium our batteries were also not 100% efficient. Magnesium has a half reaction of -2.37v and cooper has a half reaction of .337v. When you subtract the anode from the cathode you should get I.337-(-2.37)I=2.707v. This reaction should have produced enough energy to light an LED, but our batteries did not work. Again out battery was not 100% efficient. Energy could have been lost due to heat or human error.
Our project was not very efficient. In theory out battery should have been producing enough energy to light an LED, but when we tested it out it did not work. This could have because of losses on energy due to heat of human error. All of the energy in our battery was also not concentrated. If we could have found a way to concentrate the energy in our battery, we could have possibly gotten enough energy to light the LED. Also if we were to make a circuit of energy that could have produced more energy than just having one battery. Overall there where not a lot of selling points for our project, because it was so significant.
Reflection
This lab was very fun, interesting, and different. With having so much freedom with how we wanted to orient our project, it changed our group dynamic for good and in some ways bad. This project I felt like our group could have done a little batter at communicating with each other. When working together there was some times confusion on who was to do what. Secondly I felt like also could have worked on proper leadership skills and asserting myself. During this project I felt like I did what I was told well, and did all the tasks that my group members needed me to be, but I was lacking when I came to creative and new ideas. This shows how I can work on my critical learning skills. Although we has some faults, I felt like overall our group worked very well together. Our group spread out the work load very evenly through the group, and we assigned everyone positions that they felt most comfortable in. This made our work easy and productive. As a group we collaborated very well together. Lastly I felt like out group did a great job at staying on task. For all of the work days everyone showed up and was ready to work. Everyday we progressed on our project, whether it was building the project, researching, and practicing out presentation, every day we where on task. This shows our groups conciseness learning and self management skills.