Name______________ Period________ Purpose: The students will identify and construct different types of electrochemical cells. Safety Considerations: Safety is of utmost importance Electricity can be very dangerous. Do not attempt this lab if you are prone to holding wires in your mouth while standing in a bucket of water. Never use a computer while swimming. You should put on your virtual lab goggles. Materials: Volataic part of the lab: http://www.kentchemistry.com/moviesfiles/Units/Redox/VoltaicCellEMF.htm electrolysis part of the lab: http://www.kentchemistry.com/moviesfiles/Units/Redox/voltaiccelll20.htm Procedure: Visit the website above. 1. Click on the Go button next to the number 1334 2. Construct a data table: 3. Include a column for the cathode, cathode solution, anode solution, anode, # electrons moved per atom of anode metal, voltage, and cell notation 4. Create a galvanic cell using all of the combinations of metals and solutions. If no electrons move, write N/A in your data table. Return to the virtual library, 1. Click on the go button next to the number 1335. 2. Construct a data table for this experiment which has a column for each variable, predicted amount of deposition, and starting and ending masses for each electrode. 3. Choose a metal for the cathode and anode, voltage, current, time, and electrolyte. 4. Calculate the amount of deposited material on the anode (show all work) Place in data table. 5. Click the on button in the experiment, and record the masses of the electrodes at the end of the time selected. 6. Repeat the procedure for 3 other combinations of electrodes and electrolytes. Clean up and turn the computer off. Analysis Questions: Experiment 1 1) Describe the differences between the two types of cells you used today. 2) What is an electrode potential? What does a negative potential indicate? 3) What is the purpose of the salt bridge? Why must it be connected to both electrolyte solutions? 4) What combination resulted in the most active cell? Why? 5) What combinations result in a ‘dead cell’ where no reaction occurred? Explain why no electrons were moved. 6) Re-order the electrodes you used based on reduction potential. Use Copper as your standard. 7) Calculate the voltage that the first 3 voltaic cells you created would produce if the molarity of the anode solution was .001M instead of 1.0 M 8) What would happen to the voltage if the mass of the electrodes were increased? Explain. 9) Zinc and silver are used in a voltaic cell. Zinc is the anode and Silver is the cathode. If the concentration of Zinc chloride is 1M, and the voltage across the cell is 0.84 calculate: a. The concentration of silver in the half cell. b. The Ksp of silver chloride. Experiment 2 1) Describe what current is and what factor it plays in electrolysis. 2) Is this experiment spontaneous, why or why not? 3) Describe voltage and its affect on the ability to perform electrolysis.