Electrochemistry Virtual Activities AP Chemistry Date: Activity 1 Results for each combination Mg(NO 3 ) 2 Zn(NO 3 ) 2 Cu(NO 3 ) 2 AgNO 3

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1 Electrochemistry Virtual Activities AP Chemistry Name: Date: Part I :Go to and click on the Activity Series virtual activity link. (Full web address is Mg Cu Zn Ag Activity 1 Results for each combination Mg(NO 3 ) 2 Zn(NO 3 ) 2 Cu(NO 3 ) 2 AgNO 3 1) Which of the four metals you tested is the most reactive? 2) Which is the least reactive? 3) Arrange the metals in order of increasing reactivity (from least reactive to most reactive): Activity 2 Results for each combination Fe(NO 3 ) 2 Pb(NO 3 ) 2 Ni(NO 3 ) 2 Sn(NO 3 ) 2 Fe Pb Ni Sn 4) Which of the four metals you tested in Activity 2 is the most reactive? 5) Which is the least reactive? 6) Arrange the metals from Activity 2 in order of increasing reactivity (from least reactive to most reactive):

2 Activity 3 Results for each combination Fe(NO 3 ) 2 Zn(NO 3 ) 2 Cu(NO 3 ) 2 Pb(NO 3 ) 2 Fe Cu Zn Pb 7) Which of the four metals you tested in Activity 3 is the most reactive? 8) Which is the least reactive? 9) Arrange the metals from Activity 3 in order of increasing reactivity (from least reactive to most reactive): 10) Now combine your three lists of reactivity (in questions 3, 6, and 9) to create a master list of metal reactivity (or an activity series): 11) Compare the order of your list to the order on the standard reduction table on page 829 of the textbook (or back page of this packet). How does it compare? 12) Write and balance the half-reactions for three of the reactions that occurred in Activity 1: (You may use the standard reduction potential table to help.) Part II: Go to and click on the Voltaic Cell virtual activity link. (Full web address is 1) On the initial screen shown, click on the metals tab on the right side (black wire) and select. Click on the solutions tab on the right side (black wire) and select nitrate (Zn(NO 3 ) 2 ).

3 2) On the initial screen shown, click on the metals tab on the left side (red wire) and select. Click on the solutions tab on the left side (red wire) and select (II) nitrate (Cu(NO 3 ) 2 ). NOTE: Always use the salt that contains the metal ion of the metal electrode otherwise an additional variable is added to the cell complicating predictions and calculations. 3) Click on the on switch. Record the following: a. Voltage (don t forget positive or negative!) b. Direction for movement of electrons. c. Direction for movement of ions. 4) Now switch sides with the electrode and (II) nitrate solution on the right and the and nitrate solution on the left. What changes are there in the voltage, movement of electrons, and movement of ions? a. Voltage (don t forget positive or negative!) b. Direction for movement of electrons. c. Direction for movement of ions. 5) In a voltaic cell, positive ions in solution will move towards the least reactive metal electrode, causing it to become positively charged. Reduction of these positive ions takes place at this electrode and it referred to as the cathode. (RED CAT!) In turn, neutral atoms at the opposite, more reactive, electrode will lose their electrons resulting in positive ions entering solution. This produces a negative charge on this electrode. Since oxidation takes place at this electrode, it is referred to as the anode. (AN OX!) In the set-up described above, which electrode ( or ) is the cathode and which is the anode? anode = cathode = 6) Voltage is related to the activity of metals electrons will move away from a more active metal and towards a less active metal. Metal atoms will become oxidized and enter solution as ions at the more active electrode (anode), and metal ions will become reduced to a metal and plate out at the less active electrode (cathode). This simulation has three possible metals that can be used as electrodes in each half cell. Based on the activity list of metals which you formed in the first simulation, predicting the missing information in the following table (before doing the simulation!): left electrode right electrode voltage (+ or -) movement of electrons anode cathode

4 7) Now confirm your predictions by running the simulation for each of the cases above. Record the actual voltages and make any changes needed to your predictions. 8) Considering the above table, there were only three combinations that produced positive voltages. Of course the other three could have been made to show a positive voltage if the wires on the voltmeter were attached to the other electrode. By convention, voltaic cells are always written with a positive voltage indicating they are spontaneous reactions. Write the half reactions that occurred in each beaker of one of the three positive volt reactions, and using a reduction potential table, indicate the potential for each half reaction. NOTE: One half-reaction from the table will need to be reversed to make it an oxidation half-reaction. In this case be sure to switch the sign found on the reduction potential value. 9) Add together the oxidation and reduction potential values to get an overall cell potential for the three combinations that produced positive voltages. Compare this calculated potential with the measured potential in 6 & 7 above. 10) Write the net ionic equations for the reactions in 9 above. (Be sure the electrons are balanced!) 11) Now consider what effect changing concentrations will have on voltage. Perform simulations using the following electrodes, solutions, and concentrations: left electrode left solution right electrode right solution voltage 1 M Cu(NO 3 ) 2 1 M Zn(NO 3 ) 2 2 M Cu(NO 3 ) 2 1 M Zn(NO 3 ) M Cu(NO 3 ) 2 1 M Zn(NO 3 ) M Cu(NO 3 ) 2 1 M Zn(NO 3 ) M Cu(NO 3 ) 2 1 M Zn(NO 3 ) 2 1 M Cu(NO 3 ) M Zn(NO 3 ) 2 1 M Cu(NO 3 ) M Zn(NO 3 ) 2 1 M Cu(NO 3 ) M Zn(NO 3 ) 2

5 12) What is the net ionic reaction for the galvanic cell made using and? (Hint: Add the half-reactions together so that the electrons are balanced AND the voltage is positive!) 13) By considering the net ionic equation you wrote above and your completed table above, what effect does the following have on the voltage: (a) (b) (c) (d) Increasing the concentration of a reactant: Decreasing the concentration of a reactant: Increasing the concentration of a product: Decreasing the concentration of a product: Part III: Go to and click on the Electrochemistry tutorials link. (Full web address is Watch the Chapter 19 ChemTours and take notes: