Download Electrochemistry Day 2

Electrochemistry Day 3
1. A voltaic cell containing a standard Fe3+/Fe2+ electrode and a standard Ga3+/Ga
electrode is constructed and the circuit is closed. Without consulting the table of
standard reduction potentials, diagram and completely describe the cell from the
following experimental observations.
a. The mass of the gallium electrode decreases, and the gallium ion
concentration increases around that electrode
b. The ferrous ion, Fe2+, concentration increases in the other electrode
solution
2. Repeat the above problem for a voltaic cell that contains standard Co2+/Co and
Au3+/Au electrodes. The observations are
a. Metallic gold plates out on one electrode, and the gold ion concentration
decreases around that electrode
b. The mass of the cobalt electrode decreases, and the cobalt (II) ion
concentration increases around that electrode
3. Diagram the following cells. For each cell, write the balanced equation for the
reaction that occurs spontaneously, and calculate the cell potential. Indicate the
direction of electron flow, the anode, the cathode, and the polarity (+ or -) of each
electrode. In each case, assume that the circuit is completed by a wire and a salt
bridge.
a. A strip of magnesium is immersed in a solution that is 1.0M in Mg2+ and a
strip of silver is immersed in a solution that is 1.0M in Ag+.
b. A strip of nickel is immersed in a solution that is 1.0M in Ni2+, and a strip
of silver is immersed in a solution that is 1.0M in Ag+
c. A strip of chromium is immersed in a solution that is 1.0M in Cr3+ , and a
strip of gold is immersed in a solution that is 1.0M in Au3+
d. A strip of aluminum is immersed in a solution that is 1.0M in Al3+, and a
strip of copper is immersed in a solution that is 1.0M in Cu2+
Electrochemistry Day 4
4. Using a table of standard reduction potentials, determine which of the following
reactions are spontaneous under normal conditions
a. Mn + 2H+  H2 + Mn2+
b. 2Al3+ + 3H2  2Al + 6H+
c. 2Cr(OH)3 + 6F-  2Cr + 6OH- + 3F2
d. Cl2 + 2Br-1  2Cl-1 + Br2
5. Calculate E0 for the following reactions:
a. Cr3+ + Cl2 ⇄ Cr2O72- + Cl-1
b. Cu2+ + Mg ⇄ Mg2+ + Cu
c. IO3- + Fe2+ ⇄ Fe3+ + I2
d. Zn + Ag+ ⇄ Zn2+ + Ag
6. Which of the following is the stronger reducing agent
a. Ag or H2
b. Sn or Pb
c. Hg or Au
d. Cl- in acidic solution or Cl- in basic solution
e. Ag or Au
7. Which or each pair is the stronger oxidizing agent?
a. Cu+ or Ag+
b. Sn2+ or Sn4+
c. Fe2+ or Fe3+
d. I2 or Br2
e. MnO4- in acidic solution or MnO4- in basic solution
f. H+ or Cl2
8. Put the following in order of increasing strength as oxidizing agents
a. Cd2+, IO3-, K+, H2O, AuCl4, I2
9. Put the following in order of increasing strength as reducing agents
a. Cu+, F-, H2O, I2, K