1. Calculate the standard free-energy change for each of the following reactions:
    1. Cl2 + 2 Br- → 2 Cl- + Br2
    2. 3 S2O82- + 2 MnO2 + 4 H2O → 6 SO42- + 2 MNO4- + 8 H+
  2. For each of the following species determine the oxidation state of the Mn.

    KMnO4, MnO2, MnCl2

    1. Which species is the best oxidizing agent?
    2. Which species is most easily reduced?
    3. Will zinc metal reduce MnCl2 to elemental manganese?
    4. Diagram a cell that uses elemental zinc in one half reaction and MnO4- in the other. Be sure to label all parts, give the direction of electron flow, and give the polarity of the electrodes.
    5. What is the standard cell potential for the cell described in part e?
    6. What is the standard free energy change for the cell described in part e?
  3. Balance the following equations:
    1. in acid solution Cr3+ + ClO3- → Cr2O72- + ClO2
    2. in basic solution Cl2 → Cl- + ClO-
  4. What weight of chromium will be plated from a solution of Cr(NO3)3 by a current of 6.0 A in 2.0 hr?
  5. Diagram an electrolytic cell that contains an aqueous solution of cupric chloride.
    1. What products are formed at each electrode?
    2. How many grams of the product formed at the cathode will be produced by a current of 1 A operating for 4 hours?