ปฏิกิริยาไฟฟ้าเคมี Part __

俿҇ à¤ÁÕ By KruGift

Anode Oxidation : e- 1. Zn Zn Zn2+ + 2e- 2M : Zn + MnO 1. 1.5 2. NH3 NH3 H2O 3. Zn2+ [Zn(NH3)2(H2O)2]2+ [Zn(NH3)4]2+ 4. 5. H2O 2. Zn Zn + 2OH- Zn2+ + H2O + 2e- 2 1. 1.5 2. KOH 3. H2O OH-

21 Cathode Reduction : e- C MnO2 NH4Cl ZnCl2 MnO2+2 +2e- Mn2O3+H2O+2NH3 H2O O2 Zn Mn O NH + H O 0 KOH NaOH MnO2 C 2MnO2 + H2O + 2e- Mn2O3 + 2OH- KOH MnO2 : Zn + MnO ZnO Mn O MnO2 NaOH

3. Zn Zn + 2OH- Zn2+ + H2O + 2e- 1. 1.3 2. 3. 4. 4. Zn Zn + 2OH- Zn2+ + H2O + 2e- 1. 1.5 2. 3.

22 2HgO + H2O + 2e- Hg + 2OH- KOH NaOH : Zn + HgO ZnO Hg Zn(OH)2 HgO Ag2O + H2O + 2e- 2Ag + 2OH- KOH NaOH : Zn + Ag2O ZnO 2Ag Zn(OH)2 Ag2O

5. 1) H2-O2 OH- : AFC *** H2-O2 H2 Anode H + OH- H O + e- : H O2 2H O AFC 2) H2-O2 H+) H2 Anode H H+ + e- : H O2 2H O PEMFC

O2 Cathode 23 O2 + 2H2O + 4e- 4OH- KOH : PEMFC Cathode ( ) O2 2H2O O2 + H+ + 4e-

3) H2-O2 MCFC) H+ H2 Anode H O + CO + 2e- : H 1/2O2 H O H O2 MCFC) 1. H2-O2 2. H2 Anode 3. O2 Cathode H AFC H + OH- H O + PEMFC H H+ + e- MCFC H + H O + CO +

24 ) Cathode Na2CO3 O2 1/2O2 + CO + 2e- 2H O 4. H O2 2H O 5. O2 e- OH- O2 + 2H2O + 4e- 4OH- + 2e- H+ O2 + H+ + 4e- 2H2O 1/2O2 + CO + 2e-

6. Anode C3H8-O2 C3H8 Anode C3H8 + 6H2O 3CO + 20H+ + 20e- : C3H8 + 5O2 3CO + 10H2O CH O 7. (CH3OH) Anode (CH3OH) CH3OH + H2O CO2 + 6H+ + 6e- : CH3OH + 3/2O2 CO2 + 2H2O

25 Cathode O2 Cathode H2SO4 5O2 + 20H+ + 20e- 10H2O O2 Cathode 3/2O2 + 6H+ + 6e- 3H2O



26

27 1. A B C D A Zn C MnO2 KOH B ZnCl2 C Zn C , MnO2 , NH4Cl D KOH Zn HgO KOH Zn Ag2O ABCD Ent-2539 1. 2. 3. 4. 2. - Ent-2522 1. 2. H2-O2 Ent-2523 3. 4. 3. 1. 2. 3. 4. 4. - Eo Ent-2525 - 1. 2. (Eo) 25oC Eo V 1. 13 3. Ent-2533 -0.83 2. 14 4. 0.00 3. 23 0.40 4. 24 5. 1.23 1. 2H2O(l) + 2e- H2(g) + 2OH-(aq) 2. 2H+(aq) + 2e- H2(g) 3. O2(g) + 2H2O(l) + 2e- 4OH-(aq) 4. O2(g) + 4H+(aq) + 4e- 2H2O(l)

6. 1. 2H+(aq) + 2e- H2(g) Eo = 0.00 28 2. 2H2O(l) + 2e- H2(g) + 2OH-(aq) Eo = -0.83 Ent 2544 3. O2(g) + 2H2O(l) + 4e- 4OH-(aq) Eo = 0.40 4. O2(g) + 4H+(aq) + 4e- 2H2O(l) Eo = 1.23 - 1. 1 3 , 0.40 2. 2 3 , 1.23 3. 1 4 , 1.23 4. 2 4 , 2.06 7. 1. 2D+ + 2e- D2(g) Eo = 0.00 2. O2(g) + 4H+(aq) + 4e- 2H2O(l) Eo = 1.23 3. Ca2+ + 2e- 2Ca Eo = -2.87 4. ClO4- + 8H+ + 7e- 1/2Cl2 + 4H2O Eo = 1.55 5. 2H2O(l) + 2e- H2(g) + 2OH-(aq) Eo = -0.83 6. O2(g) + 2H2O(l) + 4e- 4OH-(aq) Eo = 0.40 1. 5 6 2. 5 2 3. 5 6 4. 5 2

29 1. Pb + 1. Pb - 1. H2SO4 1 2. 3. 2. 2 S2 +2e- Eo=2.05 2H++2e- H2 Eo=0.00 2H2O O2+4H++4e- Eo=1.23 2H2O+2e- H2+2OH- Eo=-0.83 Pb+O2 PbO2 2H2O+Pb PbO2+4H++4e- 2H++2e- H2 PbO2 2H++2e- H2 2H2O+Pb PbO2+4H++4e- H2 3. Anode Cathode 2H++2e- H2 Eo=0.00 Cathode Anode Pb+ +4H++2e- PbSO4+2H2O +- Eo=1.69 Pb+ PbSO4+2e- Eo=-0.36 2 S2 +2e- Eo=2.05 PbO2+ +4H++2e- PbSO4+2H2O Pb+ PbSO4+2e- PbO2+ +4H++2e- PbSO4+2H2O Pb+ PbSO4+2e- PbO2 + Pb + 2 + 4H+ 2PbSO4 + 2H2O

30 PbSO4 PbSO4 4. 2 S2 +2e- Eo=2.05 PbSO4+2e- Pb+ Eo=-0.36 PbSO4+2H2O PbO2+ +4H++2e- Eo=1.69 PbSO4+2H2O PbO2+ +4H++2e- PbSO4+2e- Pb+ +4H++2e- PbSO4+2e- Pb+ PbSO4+2H2O PbO2+ 2PbSO4 + 2H2O PbO2 + Pb + 2 + 4H+ Pb PbO2 PbSO4 + PbO2 PbSO4 PbO2 - Pb PbSO4 Pb = 2.05 V =0V = 2.05 V

31 Pb(s) + PbO2(s) + 4H+(aq) + 2SO4(aq) 2PbSO4(s) + 2H2O(l) 1. Pb(s) + PbO2(s) + 4H+(aq) + 2SO4(aq) 2PbSO4(s) + 2H2O(l) ___ 1. PbSO4 Anode Cathode ___ 2. H2O ___ 3. ___ 4. PbO2 Reduction __ 5. Pb Oxidation ___ 6. ___ 7. Anode Cathode ___ 8. Anode Cathode ___ 9. 2PbSO4(s) + 2H2O(l) Pb(s) + PbO2(s) + 4H+(aq) + 2SO4(aq) ___ 10. PbSO4 Reduction Oxidation H2SO4 2. Ent-2521 1. 3. H2SO4 2. PbO2 4. PbSO4 3. A : PbO2 s) + s) + 4H+ s) + 2e- PbSO4 s) + 2H2O s) B : Pb s) + s) PbSO4 s) + 2e- Ent-2527 1. AB + 2. 3. 4. B A 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 2. 2 3. 4

4. Ent-2538 32 1. 4 2. H2SO4 3. 4. 5. A : PbO2 s) + s) + 4H+ s) + 2e- PbSO4 s) + 2H2O s) B : Pb s) + s) PbSO4 s) + 2e- Ent- 2543 1. H2SO4 2. A Reduction B Oxidation 3. PbSO4 Anode Cathode 4. PbSO4 6. + 4H+ + 2e- PbSO4 + 2H2O A : PbO2 + PbSO4 + 2e- PbSO4 B : Pb + Ent-2529 1. Pb PbO2 2. 3. 4. 7. Pb 2H++2e- H2 Ent 1. Pb Pb2++ 2e- 2. Pb + 2H2O PbO2 + 4H+ + 4e- 3. PbSO4 + 2H2O PbO2 + H + 3H+ + 2e- 4. Pb + H PbSO4 + H+ + 2e- 8. 2. HNO3 3. PbSO4 4. H2SO4 1. HCl 6. 4 7. 2 8. 4 4. 4 5. 1

33 2. 1. Cd 1. Cd 2. III NiO(OH) 3. KOH 2. Oxidation e- Cd(s) + 2OH-(aq) Cd(OH)2(s) + 2e- 3. Reduction e- 2NiO(OH)(s) + 2H2O(l) + 2e- Cd(OH)2(s) + 2OH-(aq) 4. Cd(s) + 2NiO(OH)(s) + 2H2O(l) Cd(OH)2(s) + 2Ni(OH)2(s) Cd(OH)2(s) + 2Ni(OH)2(s) Cd(s) + 2NiO(OH)(s) + 2H2O(l) 1.2 2.

34 1. LiMnO4 LiCoO2 1. Li+ e- 2. 3. 6C + xLi+ + e- LixC6 LiCoO2 Li1-x + CoO2 + xLi+ + e- 2. 6C + LiCoO2 Li1-x + CoO2 + LixC6 3. 1. - 2. 3. 1. Al Mg Na Na+ 1. 2. Oxidation e- 2Na(l) 2Na+(l) + 2e- 3. Reduction e- n/8S8(l) + 2e- nS2-(l) 2. 2Na(l) + n/8S8(l) 2Na+(l) + nS2-(l) 3. 2Na+(l) + nS2-(l) 2Na(l) + n/8S8(l)

35 4. 2.1 1. 2. 350 oC 3. 1. Eo Eo = -0.4 V Cd(OH)2(s) + 2e- Cd(s) + 2OH-(aq) Eo = 1.0 V NiO2(s) + 2H2O + 2e- Ni(OH)2(s) + 2OH-(aq) 1. Cd(s) 2. NiO2(s) 2. Cd(s) 4. NiO2(s) Ent-2541 1. 1 3 2. 1 4 3. 2 3 4. 2 4 2. Cd(s) + 2OH- Cd(OH)2(s) + 2e- Cd(s) + NiO2(s) + 2H2O l Cd(OH)2(s) + Ni(OH)2(s) 1. 2. 3. 4.

1. 36 Eocell + 2. Eocell - Oxidation Reduction Eocell Eocell = EoCathode - EoAnode Eocell = EoCathode - EoAnode 1. 1. 2. 3. 1 H2-O2 2 AFC (3) PEMFC 2. (MCFC) C3H8-O2 - - -

37 Electholytic cell electrolysis) Electrode) Power point Iron (+) + Iron(-) Iron (+) e- Iron (-) 2 1. 1. 2.

38 1. Ex.1 NaCl Cl2 + 2e- 2Cl Eo = 1.36 V Na+ + e- Na Eo = -2.71 V 1. reduction 2. oxidation 3. (redox) 4. Eocell = 5. V 2. Na2SO4 Pt , EX2. Na+ + e- Na Eo = -2.71 V SO42- Na+ 2H2O + 2e- H2 + 2OH- E0 = -0.83 V H2O H2O 1/2S2O82- + e- SO42- Eo = 2.01 V 1/2 O2 + 2H+ + 2e- H2O Eo = 1.23 V 1. reduction 2. oxidation 3. (redox) 4. Eocell =

39 Ex3 CuSO4 Cu2+ + 2e- Cu Eo = 0.34 V Eo = 0.44 V Fe2+ + 2e- Fe E0 = -0.83 V Eo = 2.01 V 2H2O + 2e- H2 + 2OH- Eo = 1.23 V 1/2S2O82- + e- SO42- 1/2 O2 + 2H+ + 2e- H2O 1. reduction 2. 3. oxidation 4. Eocell = (redox) 3. 1. 2. 3. 1. 2H2O + 2e- H2 + 2OH- E0 = -0.83 V H+ + 2e- H2 Eo = +0.00 V 1/2 O2 + 2H+ + 2e- Eo = +1.23 V SO42- + 4H+ + 2e- H2O Eo = +0.20 V SO2 + 2H2O 1. reduction 2. oxidation 3. (redox) 4. Eocell =

40 2. 1. 2. 3. 4. 5. 3. 0.4 v Anode Cathode Ag=0.4 v Cu=0.34 v Cu=0.34 v Zn=-0.76 v Mg=-2.36 v CuSO4

41 1. 0.4 - - 1 - - 2. - - - - 1. Sn2++ 2Fe3+ Sn4+ + 2Fe2+ S + O2 SO2 S2Cl2 CaO + H2O Ca(OH)2 CH3COOC2H5 2NO + O2 2NO2 2. 2CO2 2C + O2 CS2 + 3Cl2 CCl4 + CH3COOH + C2H5OH + H2O CaCO3 CaO + CO2

42 3. 1. Al3+ + Mg Al + Mg2+ Cd2+ 2. Sn4+ + Cd Sn2+ + Mg Cd2+ 3. Mg2+ + Sn2+ Sn4+ + 34 4. Al3+ + Cd Al + 2. Ag 12 23 4. Zn 14 4. Fe3+ Na+ 1. Cu Ag+ 23 4 3. Fe Zn2+ 1 12 12 3 5. CuSO4 SnSO4 ZnSO4 Al2 (SO4)3 Al2 (SO4)3 SnSO4 Al2 (SO4)3 ZnSO4 CuSO4 SnSO4 CuSO4 ZnSO4 6. Fe Zn Al Cu Cu Fe Zn Al Al Zn Fe Cu Al Zn Cu Fe

43 7. Fe Sn2+ PAT-2 52 Fe Sn4+ E0 = -0.22 V E0 = -0.18 V Sn Fe2+ Sn Fe3+ 8. X+ + e- X Y+ + e- Y Y XCl X Y X YCl Y HCl X HCl