cells and batteries updated

Name: ______________________ Batteries Group Activity Learning Objectives Understand the basic parts of a voltaic cell Investigate lithium ion batteries Background In this part of the investigation, you will investigate a voltaic cell. You can find the simulation here: http://introchem.chem.okstate.edu/DCICLA/voltaicCell20.html. You might have to allow your browser to play adobe flash. (If you see a grey lego or puzzle piece, click on it and say “Allow Flash”) 411797514287500Initial Definitions: Make sure you start with the picture above showing. Choose copper for the red wire by clicking on the metals tab on the left. Then choose copper II nitrate (1.0 M Cu(NO3)2) as the solution in the left beaker. Then choose zinc and zinc II nitrate (1.0 M Zn(NO3)2) the right beaker. It should look like the image to the right. Then click on the four tabs to close them. Now turn the power button from off to on. (If the simulation end as you are watching it, you’ll need to reset it up again) Voltage can be described as how much “push” the moving electrons feel in a cell. What value shows on the volt meter? Is the light bulb on? Which way do the electrons move? Towards the copper metal or towards the zinc? Information: What you are looking at is a galvanic cell. In a galvanic cell energy is released (and can do work like turn on a lightbulb) by a spontaneous (happens on its own) reaction where chemical energy is converted to electrical energy. The electrons are lost at the anode and travel towards the cathode through the circuit. The solution is called the electrolyte. Using the information above, which metal is acting as the anode in your circuit? How do you know? Which metal is acting as a cathode? Now we’ll explore what happens if you change the metals and solutions in the experiment. If the simulator is still running, you’ll need to either wait for it to finish or re-load the webpage. Complete the following table Experiment Metal 1 (left) Solution 1 Metal 2 (right) Solution 2 Anode Cathode Voltage 1 Copper (Cu) Cu(NO3)2 Zinc (Zn) Zn(NO3)2 Zinc Copper 1.10 V 2 Zinc (Zn) Zn(NO3)2 Copper (Cu) Cu(NO3)2 3 Silver (Ag) AgNO3 Copper (Cu) Cu(NO3)2 4 Silver (Ag) AgNO3 Zinc (Zn) Zn(NO3)2 5 Copper (Cu) Cu(NO3)2 Copper (Cu) Cu(NO3)2 What happened when you switched the metals and solutions (look at experiment 1 and 2)? Batteries with higher voltage are more efficient. Which experiment gave the highest voltage? What happens if you make both metals and both solutions the same (experiment 5)? Explain your answer. Reset the simulation for experiment 6 and press “on.” Experiment Metal 1 (left) Solution 1 Metal 2 (right) Solution 2 6 Silver (Ag) Cu(NO3)2 Copper (Cu) AgNO3 What does the copper metal look like after the simulation? What is on the copper at the end? (hint look at the color) Where did the Ag+ ions go? Where did the Cu+2 ions come from? Electrons transferred from the copper (Cu) metal to the silver ions (Ag+). Why did the volt meter read 0? Experiment 6 is called electroplating. You used the movement of electrons between metals to coat one metal onto another. In this case silver coated copper. If you want to learn more about electroplating, watch this video: https://www.youtube.com/watch?v=OxhCU_jBiOA Model 2: Lithium Ion Cells Watch the video at https://www.youtube.com/watch?v=VxMM4g2Sk8U When the battery is being charged, which way do the electrons flow? Towards or away from the graphite? When the battery is begin used as a cell, which way do the electrons flow? Towards or away from the graphite? What is the difference between a battery and a cell? What is the anode in a lithium ion cell? What is the electrolyte in a lithium ion cell? Discuss at least one similarity and one difference between the lithium ion cell and the galvanic cell from part 1. What is happening when lithium batteries overheat and catch fire? What is done to prevent fires? What is the SEI layer? Why is it important for Li ion cells? Describe two things that you learned from this video that you found interesting or that you would like to learn more about.