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(ELECTROCHEMICAL ENGINEERING)
Chapter 2.
2.1
2.2 Nernst-Einstein
2.3 Einstein and Stokes-Einstein
2.4
2.5
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2.1
()Conductivity25S/cm()Resistivity (electric conductivity)
(1).
(2).
(3).
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T;
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2.2 Nernst-Einstein
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Perrin (0.29m)
(Jean Perrin)(colloidal particles)
()(chemical potential) mc c0x=0xP(x,t)
Nernst- Einstein Equation
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2.3 Einstein and Stokes-Einstein
R(t)x
av(Stokes)
Nernst-Einstein Equation Stokes-Einstein equation
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2.4
E=E0-(2.303RT/nF)*logQ
EE0
R8.314T
QaA+bBcC+dD
Q=[C]c[D]d/[A]a[B]b
Ag+(aq)+e-Ag(S)E0=+0.80V ([Ag+]=1.0M)
[Ag+]=0.2ME=E0-(0.0592/n)logQ
=0.80-(0.0592/1)log(1/0.2)=0.7586V
[Ag+]=2.0ME=E0-(0.0592/n)logQ
=0.80-(0.0592/1)log(1/2)=0.8178V
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electromotive forcehalf-cell
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(E) EE
(): Zn(s) Zn2+ (aq) + 2e E = 0.76 V (): Cu2+(aq) + 2e Cu(s) E = 0.34 V : Zn(s) + Cu2+(aq) Zn2+ (aq) + Cu(s) E = 1.10 V
(1).0.5MKNO3
(2).3
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:
(1).
(2).
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:
(1).
(2).
(3).Zn-Cu
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2.5
:
(Wheatstone)(ohm)(mho)
mho1 mho/cm
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(Conductivity)()(SO42-Cl-NO3-CO32-HCO3-)
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11 cm21 cm
kmho / cm = 25 km = t
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(PRINCIPLES AND APPLICATIONS OF ELECTROCHEMISTRY) ::D.R.Crow
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