Answer all questions in the space provided. Number each question in your response. Answer each question in no more than 100 words (words exceeding this limit will not be considered in grading). One or more of the following questions will be graded.
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Standard half-cell reaction
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Eo
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DGfo
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Zn2+(aq) + 2e-Zn(s)
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-0.76 V
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+147 kJ/mol
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Ni2+(aq) + 2e-Ni(s)
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-0.28 V
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+54 kJ/mol
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Pb2+(aq) + 2e-Pb(s)
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-0.13 V
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+25 kJ/mol
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Cu2+(aq) + 2e-Cu(s)
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+0.34 V
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-65 kJ/mol
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Ag+(aq) + e-Ag(s)
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+0.80 V
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-77 kJ/mol
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1. During operation of the galvanic cell shown below, Ni(s) is deposited on the electrode in the half-cell on the right hand side. Choose any half-cell from those listed in the table above that would make this occur spontaneously and then specify all the components marked in the drawing with labels I-III. (For solutions, assume the appropriate nitrate (NO3-) salts are available.)
(see attached for photo)
2. What is the direction of the electron flow in the electrical circuit connecting the electrodes?
3. Knowing that the salt bridge contains a high concentration of KNO3(aq), what is the direction in which nitrate anions migrate?
4. Consider again the table of data above. How many different galvanic cells can you build, using the five half-cells in the table, in which a solid lead electrode would decrease its mass? Calculate the cell potential, DEOCell in all of those cases.