Electrochem- Some Review and Some New
1.
Cr2O72-(aq) + U4+ (aq)
Cr3+ (aq) + UO22+ (aq); ACIDIC solution
a. Write the half reaction for the cathode?
b. Write the half reaction for the anode?
c. What species is the reducing agent in this oxidation reduction reaction?
2. Which one of these species would make the best oxidizing agent in a redox reaction?
Eu3+ (aq) + 3e-
Eu(s)
E0 = -1.991 V
Au3+ (aq) + 2e-
Au+
E0 = +1.41 V
In3+ (aq) + 3e-
In (s)
E0 = -0.338 V
Li+ (aq) + e-
Li(s)
E0 = -3.040 V
3. . Write the Nearnst Equation for the following reaction. E0 = -0.12V
CrO42- (aq) + 4H2O(l) +3e-
Cr(OH)3(s) + 5OH-
4. a. Determine the cell potential for a cell made up of 1M Ag+ with a Ag(s) electrode and 1M
Cd+2 with a Cd(s) electrode.
E0 Ag+/Ag(s) = 0.799 V
E0 Cd2+/Cd(s) = -0.402 V
b. Determine the cell potential for a cell made up of 0.50 M AgNO3(aq) with a Ag(s) electrode
and 0.010 M Cd(NO3)2 (aq).
E0 Ag+/Ag(s) = 0.799 V
E0 Cd2+/Cd(s) = -0.402 V
5. Would the following cell work? Why or why not?
E0 for Ag+/ Ag(s) = +0.799 V
E0 for Fe+3/ Fe+2
= +0.771 V
-
+
Ag(s)
Pt
1M Fe+3
1M Fe+2
0.1M
Ag+
6. Will the following cell work to the best of its ability as diagramed below? Answer
YES or NO. Provide a detailed explanation along with your Yes or No answer for
FULL CREDIT.
Some of the following information may be helpful
E0 for Cl2(g)/ Cl- = +1.359 V
E0 for Ag+/ Ag(s)
E0 for Cr+3/ Cr(s)
= -0.744 V
E0 for Cr+3/ Cr+2
= -0.408 V
-
+V
E0 for Ag2+/ Ag+
+
Ag(s)
Pt(s)
CrCl3(aq)
CrCl2(aq)
AgNO3(aq)
b. Why is Pt one of the electrodes used in this electrochemical cell?
= +0.799 V
= +1.989 V