1. List the cations and their oxidation state that make up Group II. (2 pt ea)
XtraCredit-list the colors of these ions in solution (1 pt ea)

2. List the cations and their oxidation state that make up Group III. (2 pt ea)
XtraCredit-list the colors of these ions in solution (1 pt ea)

3. One common problem in qual procedures is the generation of elemental sulfur when nitric acid is used on sulfide ppts. Write the unbalanced overall reaction and the two balanced half cells showing nitrate ion reacting with As2S5 to give arsenate ion and sulfur. Nitrate ion forms NO2 gas.
(No need to balance the overall reaction)

4. Given an unknown containing both nitrate and iodide ions, would you predict that the iodide ion could be oxidized to iodine by nitrate ion? Write the proposed reaction and use standard half cell potentials to make this prediction. The nitrate half cell is the same as prob. #3 above.

5. Calculate the Ksp of lead sulfate using half cell data. Start by writing the Ksp equilibrium. (I will provide the needed half cells for 2 pt ea. if you can't figure out which ones to use.)

You are given strips of Cd and Cu metals and 1.0 M solutions of CdCl2 and CuCl2
with which to construct a battery.

6. Determine the spontaneous redox reaction and the standard cell potential. (Chloride ion is not involved here)

7. If I use 0.10 M CdCl2 instead of 1.0 M, what will be the cell voltage?
(Cu+2 is still 1M)

8. Label the accompanying diagram showing the proper arrangement of materials.

9. Calculate the current, in amps, required to deposit 1.00 lb of aluminum per minute in an industrial cell. (Use Al+3 + 3e- ---> Al, 1F=96,485 C/mole e-, 1Amp=1C/sec, MWt of Al=26.98 gm/mole, 1 lb=454 gm)