1. Balance the following oxidation-reduction (redox) reactions using the half reactions method. All three reactions are acidic and the ionic species in the reaction are aqueous
a. NO3- + Cu(s) -->ï NO(g) + Cu2+
b. S2O32- + IO3- -->ï SO42- + I-
2. Balance the following redox reaction in basic solution. P(s) + SO42- --> ï PO43- + SO32
3.a) On the galvanic cell shown below, label the anode on the left and cathode on the right. Labels should include all four constituents of the reaction. Indicate electron flow with an arrow. Place a salt bridge in the cell (e.g. KNO3) and show cation/anion movement. Ag+(aq) + Zn(s) --> Ag(s) + Zn2+(aq) (unbalanced)
b) As the reaction proceeds, do you expect...
i.The mass of the anode electrode to increase?
ii.The mass of the cathode electrode to increase?
iii.[Ag+] to increase OR decrease?
iv.[Zn2+] to increase OR decrease?
c) Does oxidation occurs at the: Anode or cathode?
d) Write the two half reactions and balance the redox reaction:
e) Write the cell in shorthand notation.
4. Consider the cell: Cd(s) | Cd2+(aq) || Ni2+(aq) | Ni(s)
a. Write the half reaction for the anode and look up its E0 value.
b. Write the half reaction for the cathode and look up its E0 value.
c. Combine the two half reactions to get the balanced redox reaction and calculate E0 value for the galvanic cell.
d. Calculate ïG0rxn
e. What is the expected value for potential cell, Erxn, if [Cd2+] = 0.10M and [Ni+] = 0.50 M?
5. Consider the following list of species: Cd(s); Cd2+(aq); Ni(s); Ni2+(aq) Cu(s); Cu2+(aq) Ag(s); Ag+(aq)
a. Which one is the best oxidizing agent from this list?
b. Which one is the best reducing agent from this list?
c. Which one is the most easily oxidized from this list?
d. Which one is the most easily reduced from this list?
e. Determine E0 for the most spontaneous combination of half cells from the list â in other words which cell gives the highest value for E0.
6. Based on the balanced chemical equation shown below, determine the molarity of the solution containing Fe2+, if 40.00 mL of Fe2+ solution is required to completely react with 30.00 mL of a 0.125 M potassium bromate, KBrO3, solution. 6Fe2+ + BrO3- -->ï Fe3+ + Br- + 3H2O
7.During an electrochemical reaction, electrons move through the external circuit toward the ____and positive ions in the cell move toward the____.
a. Anode, anode b. Cathode, anode C. Anode, cathode D. cathode, cathode
8. What is the short hand notation that represents the following galvanic cell: Fe(s) + Cu(NO3)2(aq) --> ï Fe(NO3)2(aq) + Cu(s)
a. Fe(s) | Fe2+(aq) || Cu2+(aq) | Cu(s)
b. Cu(s) | Cu2+(aq) || Fe2+(aq) | Fe(s)
c. Fe(s) | NO3-(aq) || NO3-(aq) | Cu(s)
d. Cu(s) | Cu(NO3)2(aq) || Fe(NO3)2(aq)| Fe(s)
9.In the galvanic cell: Pb(s) |Pb2+(aq) || Hg2+(aq) | Hg(s) which electrode will gain mass?
a) The anode, Pb(s);
b) The anode, Hg(s);
c) the cathode, Pb(s)
d) the cathode, Hg(s)
10. The standard cell potential for the dry cell battery (such as AA or AAA, etc.) is 1.56 V. What is the standard free energy change for this cell? Zn(s) + 2MnO2(s) + 2 NH4+ -->ï 2 N H3 + Mn2O3(s) + Zn2+ + H2O(al)
11.The standard potential for the following galvanic cell is + 0.90 V: 3Cu2+(aq) + 2Ga(s) --> ï 3Cu(s) + 2Ga3+(aq) Given that the standard reduction potential for the Cu2+/Cu hal-cell is +0.34 V, what is the standard reduction potential for the Ga3+/Ga half-cell?
12. A galvanic cell consist of these half cells: Ag+(aq) + e --> Ag(s) E0 = +0.80 V
Cu2+(aq) + 2e-->Cu(s) E0 = +0.34 V
What is formed at cathode and anode respectively?
A. Ag(s) and Cu(s)
B. Ag(s) and Cu2+(aq)
C. Cu(s) and Ag+(aq)
D. Cu2+(aq) and Cu(s)