# Electrochemistry: Voltaic Cells lab report data analysis

*label*Chemistry

*timer*Asked: Apr 8th, 2015

**Question description**

Data Analysis

1. (Part I) Compare the average cell
potential, for your Cu/Pb cell, with the E^{°}_{cell} that you
calculated in the pre-lab exercise. Explain why your cell potential is
different from the text value.

2. (Part II) The unknown metals X and Y were either magnesium, silver, or zinc. Use the text value for the reduction potential of Pb and the measured cell potentials for the unknowns to identify X and Y.

3. (Part III) Use the Nernst equation to
calculate the theoretical value of *E*
of the copper-concentration cell and compare this value with the cell potential
that you measured.

4. (Part III) Use the Nernst equation and
the information that you collected about the Pb/PbI_{2} cell to
complete the following calculations.

a. Use the cell potential for the Pb-PbI_{2}
cell and the known [Pb^{2+}] to calculate the [Pb^{2+}] in
equilibrium with PbI_{2}.

b. Use the original diluted [Pb^{2+}]
and [I^{–}] to calculate the [I^{–}] in solution.

c. Use your data to calculate the *K _{sp}* of PbI

_{2}.

d. The accepted value of the *K _{sp}* of PbI

_{2}is 9.8 × 10

^{–9}. How does your experimental

*K*of PbI

_{sp}_{2}compare with the accepted value?