PRACTICE QUIZ ELECTROCHEMISTY 20 points

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PRACTICE QUIZELECTROCHEMISTY(20 points)
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• 1. (2 points each) Circle T (True) or F (False).
• T F a. ClO- is the oxidizing agent in the rxn
• 2 OH- 4 ClO- S2O32- ? 4 Cl- 2 SO42-
  H2O.
• T F b. In the electrolysis of molten NaCl, the
  anode half-reaction is Na e- ? Na.
• T F c. The cathode of a lead storage battery
  when it is discharging is Pb. The equation is
  Pb(s) PbO2(s) 2H 2HSO4- ? 2H2O 2PbSO4(s)
• T F d. Electrons are always lost at the anode.

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• 2. Given the following reduction potentials,
• (1) Cl2 2e- ? 2Cl- E 1.36 v
• (2) Fe3 e- ? Fe2 E 0.77 v
• (3) Fe2 2e- ? Fe E -0.44 v
• (4) Mg2 2e- ? Mg E -2.37 v
• a. (1 point) Which is the strongest reducing
  agent?
• b. (7 points) Draw a diagram for a working
  voltaic cell using half-reactions (1) and (3).
  Label all parts, including direction of electron
  flow, direction of anion flow, the anode, the
  cathode, the ions in solution, and the salt
  bridge. Calculate E for the cell?

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• 3. (4 points) Combine the following
  half-reactions into a balanced overall equation
• H2S(aq) ? 2H(aq) S(s) 2e-
• 6e- 14H(aq) Cr2O72-(aq) ? 2Cr3(aq)
  7H2O(l)