Лекции по электрохимии. Учебное пособие для педагогического вуза
.pdf4. Стандартные окислительно-восстановительные потенциалы некоторых
полуреакций и их температурные коэффициенты
Полуреакции |
Eo, В (25 оС) |
|
dE o |
, мВ/К |
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dT |
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F2 + 2H+ + 2e = 2HF(aq) |
+3,06 |
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–0,60 |
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F2 + 2e = 2F– |
+2,866 |
|
+1,830 |
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MnO4– + 4H+ + 3e = MnO2 + 2 H2O |
+1,695 |
|
–0,666 |
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MnO4– + 8H+ + 5e = Mn2+ + 4 H2O |
+1,51 |
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–0,661 |
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PbO2 + 4H+ + 2e = Pb2+ + 2 H2O |
+1,455 |
|
–0,238 |
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ClO3– + 6H+ + 6e = Cl– + 3 H2O |
+1,45 |
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–0,496 |
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Cl2 + 2e = 2Cl– |
+1,35828 |
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–1,2444 |
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Cr2O72– + 14H+ + 6e= 2Cr3+ + 7 H2O |
+1,33 |
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–1,263 |
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2NO3– + 12H+ + 10e = N2 + 6 H2O |
+1,24 |
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– |
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MnO2 + 4H+ + 2e = Mn2+ + 2 H2O |
+1,23 |
|
–0,661 |
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Br2(aq)+ 2e = 2Br– |
+1,0874 |
|
–0,5406 |
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Br2(ж)+ 2e = 2Br– |
+1,0652 |
|
–0,629 |
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NO3– + 10H+ + 8e = NH4+ + 3 H2O |
+0,87 |
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– |
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NO3– + 2H+ + e = NO2 + H2O |
+0,80 |
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– |
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MnO42–+2H2O + 2e = MnO2 + 4 OH– |
+0,603 |
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– |
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MnO4– + e = MnO42– |
+0,558 |
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– |
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I2 + 2e = 2I– |
+0,5355 |
|
–0,148 |
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Ag(NH3)2+ +e=Ag +2 NH3 (aq) |
+0,373 |
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–0,460 |
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Hg2Cl2 + 2e = 2Hg + 2 Cl– |
+0,2676 |
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–0,317 |
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AgCl + e = Ag + Cl– |
+0,2222 |
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–0,658 |
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SO42– + 4H+ + 2e =H2SO3(aq) + 2 |
+0,172 |
|
+0,81 |
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H2O |
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SO42– + 8H+ + 8e = S2– + 4 H2O |
+0,149 |
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– |
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C(графит) + 4H+ + 4e= CH4 (г) |
+0,1316 |
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–0,209 |
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71
Полуреакции |
Eo, В (25 оС) |
|
dE o |
, мВ/К |
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dT |
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HgO + H2O + 2e = Hg + 2 OH– |
+0,098 |
|
–1,120 |
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AgBr + e=Ag + Br– |
+0,0713 |
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–0,508 |
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Cu(NH3)4 2+ + 2e = Cu + 4 NH3 (aq) |
–0,05 |
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– |
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CO2(г) + 2H+ + 2e = CO(г) + H2O |
–0,12 |
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– |
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CuI + e = Cu + I– |
–0,1852 |
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–0,200 |
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Ag(CN)2– +e=Ag + 2CN– |
–0,31 |
|
+0,087 |
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Cu(CN)2– +e = Cu + 2CN– |
–0,429 |
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– |
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CdSO4. (8/3)H2O+2e=Cd(Hg)+ SO42– |
–0,435 |
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– |
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S + 2e = S2– |
–0,48 |
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–0,93 |
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Au(CN)2– +e= Au + 2CN– |
–0,611 |
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– |
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Ag2S+2e=2Ag + S2– |
–0,66 |
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–1,08 |
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SO32– + 3H2O + 4e = S + 6 OH– |
–0,66 |
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– |
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SO42– + H2O + 2e = SO32– + 2 OH– |
–0,93 |
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–1,389 |
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Cr(OH)3 + 3e = Cr + 3 OH– |
–1,48 |
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–0,98 |
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Mg(OH)2 + 2e = Mg + 2 OH– |
–2,690 |
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–0,945 |
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5. Стандартные электродные потенциалы металлов и их температурные
коэффициенты
Полуреакции |
Eo, В (25 оС) |
|
dE o |
, мВ/К |
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dT |
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Li+ + e = Li |
–3,045 |
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–0,534 |
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K+ + e = K |
–2,925 |
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–1,080 |
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Cs+ + e = Cs |
–2,923 |
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–1,197 |
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Ba2+ |
+ 2e |
= Ba |
–2,906 |
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–0,395 |
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Сa2+ |
+ 2e |
= Сa |
–2,866 |
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–0,175 |
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Na+ + e = Na |
–2,714 |
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–0,772 |
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La3+ |
+ 3e |
= La |
–2,522 |
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+0,085 |
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72 |
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Полуреакции |
Eo, В (25 оС) |
dE o |
, мВ/К |
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dT |
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Ce3+ + 3e |
= Ce |
–2,483 |
+0,101 |
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Gd3+ + 3e |
= Gd |
–2,397 |
+0,147 |
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Mg2+ + 2e |
= Mg |
–2,363 |
+0,103 |
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Am3+ +e = Am |
–2,32 |
+0,089 |
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Ho3+ + 3e |
= Ho |
–2,319 |
+0,161 |
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Al 3+ + 3e = Al |
–1,662 |
+0,504 |
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Hf4+ + 4e |
= Hf |
–1,7 |
0 |
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Mn2+ + 2e |
= Mn |
–1,180 |
–0,08 |
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Zn2+ + 2e |
= Zn |
–0,76288 |
+0,091 |
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Cr3+ + 3e |
= Cr |
–0,744 |
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– |
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Ga3+ + 3e |
= Ga |
–0,529 |
+0,67 |
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Fe2+ + 2e |
= Fe |
–0,4402 |
+0,052 |
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Cd2+ + 2e |
= Cd |
–0,4029 |
–0,093 |
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In3+ + 3e |
= In |
–0,343 |
+0,4 |
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Сo2+ + 2e |
= Co |
–0,277 |
+0,06 |
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Ni2+ + 2e |
= Ni |
–0,250 |
+0,06 |
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Mo3+ + 3e |
= Mo |
–0,200 |
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– |
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Sn2+ + 2e |
= Sn |
–0,136 |
–0,282 |
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Pb2+ + 2e |
= Pb |
–0,126 |
–0,451 |
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Fe3+ + 3e |
= Fe |
–0,036 |
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– |
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Ge2+ + 2e |
= Ge |
0,0 |
|
– |
2H+ + 2e = H2 |
0,0000 |
0,000 |
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Bi3+ |
+ 3e |
= Bi |
+0,2 |
– |
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Cu2+ |
+ 2e |
= Cu |
+ 0,337 |
0,008 |
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Co3+ |
+ 3e |
= Co |
+ 0,4 |
– |
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Hg22+ + 2e = 2Hg |
+0,788 |
– |
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Ag+ + e = Ag |
+ 0,7991 |
–1,000 |
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73 |
|
Полуреакции |
Eo, В (25 оС) |
|
dE o |
, мВ/К |
|||
dT |
|||||||
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Hg2+ |
+ 2e |
= Hg |
+ 0,854 |
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– |
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Pt2+ |
+ 2e |
= Pt |
+ 1,2 |
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– |
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Au 3+ + 3e = Au |
+1,498 |
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– |
|||
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Ce4+ |
+ 4e |
= Ce |
+1,68 |
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– |
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74
