IB Chemistry II Lab: Voltaic Cells
Purpose: To construct two voltaic cells and compare the experimental potential difference to the expected potential difference
given by the standard electrode potential chart.
Expected Cell Potentials.
Metals available: Nickel, Aluminum, Zinc, Copper, Lead, Iron
You will make TWO different voltaic cells of your choice.
1.
2.
Choose your combination of metals that you wish to make your voltaic cells out of.
For each of the cells:
a. Draw an appropriately labeled diagram for the voltaic cell.
b. Write the half reactions for each electrode with standard reduction potentials.
c. Write the overall, balanced reaction for the entire cell, including the overall cell potential.
IB Chemistry II Lab: Voltaic Cells
Purpose: To construct two voltaic cells and compare the experimental potential difference to the expected potential difference
given by the standard electrode potential chart.
Expected Cell Potentials.
Metals available: Nickel, Aluminum, Zinc, Copper, Lead, Iron
You will make TWO different voltaic cells of your choice.
1.
2.
Choose your combination of metals that you wish to make your voltaic cells out of.
For each of the cells:
a. Draw an appropriately labeled diagram for the voltaic cell.
b. Write the half reactions for each electrode with standard reduction potentials.
c. Write the overall, balanced reaction for the entire cell, including the overall cell potential.
Procedure:
(Generalities for each cell)
Salt Bridge: You will make your salt bridges by soaking small, narrow strips of filter paper in 1 M KNO 3 solution. Obtain about 25 mL
of the solution in a small beaker and have your strips soaking.
Metals: Obtain strips of your two metals for each voltaic cell. Make sure they are clean by wiping with steel wool if needed. These
will need to be cleaned and returned when finished for reuse!
Half-cell containers: We will be carrying out these in petri dishes. Find the appropriate nitrate or sulfate to put in each half cell and
place each strip upright in its appropriate solution. Connect the cells using one of the salt bridges.
Measuring cell potentials: *Keep the meter’s metal contacts out of the solutions at ALL times! The black (negative) electrode
should be on the anode and the red (positive) electrode should be on the cathode. If you get a negative reading, try switching the
electrodes. Record this experimental potential in an appropriate data table.
Disposal: Dry off your metal strips and return them to the appropriate zip lock bag. Please pour solutions into their appropriate
waste beaker. The filter papers can be thrown away, but pour salt bridge solution back in ORIGINAL container (these are reused for
this lab).
Data Analysis:
Calculate the percent error for your voltaic cells. Show all work in a well-labeled, neat manner.
Procedure:
(Generalities for each cell)
Salt Bridge: You will make your salt bridges by soaking small, narrow strips of filter paper in 1 M KNO 3 solution. Obtain about 25 mL
of the solution in a small beaker and have your strips soaking.
Metals: Obtain strips of your two metals for each voltaic cell. Make sure they are clean by wiping with steel wool if needed. These
will need to be cleaned and returned when finished for reuse!
Half-cell containers: We will be carrying out these in petri dishes. Find the appropriate nitrate or sulfate to put in each half cell and
place each strip upright in its appropriate solution. Connect the cells using one of the salt bridges.
Measuring cell potentials: *Keep the meter’s metal contacts out of the solutions at ALL times! The black (negative) electrode
should be on the anode and the red (positive) electrode should be on the cathode. If you get a negative reading, try switching the
electrodes. Record this experimental potential in an appropriate data table.
Disposal: Dry off your metal strips and return them to the appropriate zip lock bag. Please pour solutions into their appropriate
waste beaker. The filter papers can be thrown away, but pour salt bridge solution back in ORIGINAL container (these are reused for
this lab).
Data Analysis:
Calculate the percent error for your voltaic cells. Show all work in a well-labeled, neat manner.