Order the following oxidizing agents by increasing strength under standard-state conditions:  1. Ag+(aq) 2. Cd2+(aq) 3. MnO42-(aq) in acidic conditions The standard reduction half-reactions and standard reduction potentials for the above species are as follows: 1. Ag+(aq) + 1e- <=> Ag(s)     Eo = +0.80 V 2. Cd2+(aq) + 2e- <=> Cd(s)   Eo = - 0.40 V 3. MnO4-(aq) + 8 H+(aq) + 5e- <=> Mn2+(aq) + 4 H2O(l)    Eo = + 1.49 V

4. A cell uses the following reaction: a. Zn (s) + 2 H* (aq) → Zn²* (aq) + H2 (g) (a) Determine the emf of the cell under standard conditions. (b) When PH,=1.0 atm and [Zn²*] = 1.0 M, the cell potential is 0.560 V. Determine the concentration of H* in the cathode compartment. Zn2“(aq) + 2e¯ → Zn(s) -0.763 2H*(aq) + 2e¯ –→ H2(g) b.

A galvanic cell is prepared according to the redox reaction shown below. A voltmeter connected to this galvanic cell under standard conditions reads 0.45 V, and AG, xn = -79 kJ/mol. If the concentration of Fe2+ is increased to 2.0 M, then Ecell will and AGrxn will be than AGxn- Fe(s) + 2H*(aq) Fe2* + H2(g) decrease, less negative O decrease, more negative O increase, more negative O increase, less negative

A chemist designs a galvanic cell that uses these two half-reactions: half-reaction standard reduction potential 2+ Zn (aq)+2e - Zn(s) :-0.763 V (red |Cro (aq)+4 H2O(1)+3e Cr(OH)3(s)+5OH (aq) :-0.13 V = - (red Answer the following questions about this cell. Write a balanced equation for the half-reaction that happens at the cathode. x10 Write a balanced equation for the half-reaction that happens at the anode. Write a balanced equation for the overall reaction that powers the cell. Be sure the reaction is spontaneous as written.

Consider the electrolysis reactions cathode anode whose standard reduction potentials can be found in this table. Calculate the voltage needed to drive the net reaction if the current is negligible. Ecell = Cu²+ (aq, 0.177 M) +2e=Cu(s) H₂O(1) ⇒ 10₂(g, 1 bar) + 2 H+ (aq, 0.195 M) + 2 e¯ The cell has a resistance of 66.0 and a current of 7.17 mA when the cathode overpotential is 0.231 V and the anode overpotential is 0.050 V. Calculate the voltage needed to overcome these effects and drive the net reaction. Ecell = V V

5. A more complex example where other atoms are involved. Balance the following reaction in basic solution. r (aq) + MnO4 (aq) MnO, (s)+ BrO;" (aq) TABLE 19.1 Standard Electrode Potentials at 25 °C Reduction Half-Reaction E'(V) F + 20 H,0,(aq) + 2 H(aq)+2 e 2F(aq) 2.87 Stronger oxidizing agent Weaker 2 H,0 - PBSO (s) +2 H,0) -Mn0(s)+ 2 H,0) Mn (aq) 4 H,O) - Auts) 1.78 reducing agent PO,(s) + 4 H"(ag) + S0,2-(aq) + 2 e 1.69 Mno, (aq)+ 4 H'(aq) 3 e Mno, (aa) + 8 H (aq)+5 e Au (aq)+3e PbO,(s)+ 4 H(aa) + 2 e Cl,(g) + 2 e" 1.68 1.51 1.50 1.46 - P (ag) + 2 HO - 2a(aq) 1.36 1.33 Cr0, (aq) + 14 H'(ag) + 6 e 0+ 4 H (aq) + 4 e MnO(s)+4 H'(aq) +2 e 10, (aq) 6 H'(aq) + 5e Br+2e vo, (aq) + 2 H'(aq) + e NO, (aq) + 4 H°(aq) + 3e CIO+e 2 C"(aq) + 7 H,On - 2 H,O1) 1.23 Mn (aq) + 2 HyOV) 121 ulae) + 3 H,0() 2 Br (ag) - vo"(aq) +H,00 - NO + 2 H,O0 - CIO, (aa) - Agis) 1.20 1.09 1.00 0.96 0.95 Ag"(aa) + e 0.80 Fe (aq) + O+2 H'(aq)+2e - Fe*(aq) 0.77 - H,O,(ag) 0.70 Mn0, Taa) + e Mn0 (aa) 0.56 8) + 2 e…

Determine the cell potential for the following cell Ni(s) | Ni2+(aq), 0.500 M || Ag+(aq), 0.010 M | Ag(s) The standard reduction potentials of Ni2+(aq) and Ag+(aq) are –0.25 V and +0.80 V, respectively.   A.  1.05 V   B.  1.10 V   C.  1.00 V   D.  1.16 V   E.  0.94 V

Calculate the theoretical cell potential for the following galvanic cell: Mg | Mg2+ ( 1 M) || Cu2+ (2 M) | Cu