Standard Reduction (Electrode) Potentials at 25 °C Half-Cell Reaction E° (volts) F2(g) + 2 e→2 F(aq) 2.87 Ce4*(aq) + e –→ Ce"(aq) 3+ 1.61 2+ MnO4 (aq) + 8 H"(aq) + 5 e¯ –→ Mn-T(aq) + 4 H2O(1) 1.51 Cl2(g) + 2 e' —2 СГ (aq) 1.36 Cr2072"(aq) + 14 H*(aq) + 6 e¯ →2 Cr"(aq) + 7 H2O(1) 1.33 O2(g) + 4 H*(aq) + 4 e→2 H2O(1) 1.229 Br2(1) + 2 e¯ –→2 Br¯(aq) 1.08 NO3 (aq) + 4 H"(aq) +3 e¯ –→ NO(g) + 2 H2O(1) 0.96 2 Hg-*(aq) + 2 e¯ → Hg22 (aq) 0.920 Hg-"(aq) + 2 e →Hg(1) 0.855 Ag"(aq) + e¯ – Ag(s) 0.799 2+, Hg2"(aq) + 2 e¯ →2 Hg(1) 0.789 Fe*(aq) + e → Fe2*(aq) 0.771 I2(s) + 2 e → 2 1 (aq) 0.535 Fe(CN)6° (aq) + e→ Fe(CN)64 (aq) 0.48 Cu2*(aq) + 2 e → Cu(s) 0.337 Cu2*(aq) + e" – Cu"(aq) 0.153 S(s) + 2 H*(aq) + 2 e → H2S(aq) 0.14 2 H*(aq) + 2 e → H2(g) 0.0000 Pb2*(aq) + 2 e → Pb(s) -0.126 Sn-"(aq) + 2 e¯ → Sn(s) „2+ -0.14 Ni2+(ag) + 2 e →Ni(s) -0.25 Co2+(ag) + 2 e →Co(s) -0.28 Cd2*(aq) + 2 e →Cd(s) -0.403 Cr3+ C* (aq) (aq) + e -0.41 Fe2*(aq) + 2 e →Fe(s) -0.44 Cr3+ (aq) + 3 e → Cr(s) -0.74 Zn2*(aq) + 2 e →Zn(s) -0.763 2 H20(1) + 2 e → H2(g) + 2 OH (aq) -0.83 Mn-"(aq) + 2 e¯ → Mn(s) 2+ -1.18 Als*(aq) + 3 e → Al(s) -1.66 2+ Mg"(aq) + 2 e →Mg(s) -2.37 Na"(aq) + e –→ Na(s) -2.714 K(aq) + e→ K(s) -2.925 Li*(aq) + e Li(s) -3.045

Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
Question
100%
When the Hg2+ concentration is 1.23 M, the observed cell potential at 298K for an electrochemical cell with the following reaction is 1.667V. What is the Cr3+ concentration?

3Hg2+(aq) + 2Cr(s)3Hg(l) + 2Cr3+(aq)

Answer: __ M

 

***************

The Nernst Equation

A non-standard cell or half-cell potential can be calculated using the Nernst Equation:

 

E = E- RT/nF (ln Q)

where

E   =   potential under non-standard conditions
Eo   =   standard potential
R   =   ideal gas constant
T   =   kelvin temperature
n   =   number of moles of electrons for the reaction as written
F   =   charge carried by 1 mol of electrons
Q   =   reaction quotient


It is customary to use the equation in a form where numerical values are substituted for R, T and F at a temperature of 25 °C.

 

For
  R   =   8.314 J mol-1K-1
  T   =   298.15 K
  F   =   96,485 J V-1 mol-1

RT/F = (8.314 J mol-1 K-1)(298.15 K)/((96,485 J V-1 mol-1)) = 0.0257 V

and the Nernst equation with the potentials in volts is:

E = E- (0.0257/n) ( ln Q)

nautral logarithm

 


Sometimes it is more convenient to use base-10 logarithms, and the substitution of 2.303 log for ln is made. (2.303 × 0.0257 = 0.0592)  Then, the Nernst equation for base-10 logs at 25 °C is:

E = E- (0.0592/n)( log Q)

base-10 logarithm

 

A common student error is to use the wrong kind of logarithm. Be sure, when you choose an equation, to use the correct logarithm.

Standard Reduction (Electrode) Potentials at 25 °C
Half-Cell Reaction
E° (volts)
F2(g) + 2 e→2 F(aq)
2.87
Ce4*(aq) + e –→ Ce"(aq)
3+
1.61
2+
MnO4 (aq) + 8 H"(aq) + 5 e¯ –→ Mn-T(aq) + 4 H2O(1)
1.51
Cl2(g) + 2 e' —2 СГ (aq)
1.36
Cr2072"(aq) + 14 H*(aq) + 6 e¯
→2 Cr"(aq) + 7 H2O(1)
1.33
O2(g) + 4 H*(aq) + 4 e→2 H2O(1)
1.229
Br2(1) + 2 e¯ –→2 Br¯(aq)
1.08
NO3 (aq) + 4 H"(aq) +3 e¯ –→ NO(g) + 2 H2O(1)
0.96
2 Hg-*(aq) + 2 e¯ →
Hg22 (aq)
0.920
Hg-"(aq) + 2 e →Hg(1)
0.855
Ag"(aq) + e¯ – Ag(s)
0.799
2+,
Hg2"(aq) + 2 e¯ →2 Hg(1)
0.789
Fe*(aq) + e →
Fe2*(aq)
0.771
I2(s) + 2 e → 2 1 (aq)
0.535
Fe(CN)6° (aq) + e→ Fe(CN)64 (aq)
0.48
Cu2*(aq) + 2 e → Cu(s)
0.337
Cu2*(aq) + e" – Cu"(aq)
0.153
S(s) + 2 H*(aq) + 2 e → H2S(aq)
0.14
2 H*(aq) + 2 e → H2(g)
0.0000
Pb2*(aq) + 2 e → Pb(s)
-0.126
Sn-"(aq) + 2 e¯ → Sn(s)
„2+
-0.14
Ni2+(ag) + 2 e →Ni(s)
-0.25
Co2+(ag) + 2 e →Co(s)
-0.28
Cd2*(aq) + 2 e →Cd(s)
-0.403
Cr3+
C* (aq)
(aq) + e
-0.41
Fe2*(aq) + 2 e →Fe(s)
-0.44
Cr3+
(aq) + 3 e → Cr(s)
-0.74
Zn2*(aq) + 2 e →Zn(s)
-0.763
2 H20(1) + 2 e → H2(g) + 2 OH (aq)
-0.83
Mn-"(aq) + 2 e¯ → Mn(s)
2+
-1.18
Als*(aq) + 3 e → Al(s)
-1.66
2+
Mg"(aq) + 2 e →Mg(s)
-2.37
Na"(aq) + e –→ Na(s)
-2.714
K(aq) + e→ K(s)
-2.925
Li*(aq) + e Li(s)
-3.045
Transcribed Image Text:Standard Reduction (Electrode) Potentials at 25 °C Half-Cell Reaction E° (volts) F2(g) + 2 e→2 F(aq) 2.87 Ce4*(aq) + e –→ Ce"(aq) 3+ 1.61 2+ MnO4 (aq) + 8 H"(aq) + 5 e¯ –→ Mn-T(aq) + 4 H2O(1) 1.51 Cl2(g) + 2 e' —2 СГ (aq) 1.36 Cr2072"(aq) + 14 H*(aq) + 6 e¯ →2 Cr"(aq) + 7 H2O(1) 1.33 O2(g) + 4 H*(aq) + 4 e→2 H2O(1) 1.229 Br2(1) + 2 e¯ –→2 Br¯(aq) 1.08 NO3 (aq) + 4 H"(aq) +3 e¯ –→ NO(g) + 2 H2O(1) 0.96 2 Hg-*(aq) + 2 e¯ → Hg22 (aq) 0.920 Hg-"(aq) + 2 e →Hg(1) 0.855 Ag"(aq) + e¯ – Ag(s) 0.799 2+, Hg2"(aq) + 2 e¯ →2 Hg(1) 0.789 Fe*(aq) + e → Fe2*(aq) 0.771 I2(s) + 2 e → 2 1 (aq) 0.535 Fe(CN)6° (aq) + e→ Fe(CN)64 (aq) 0.48 Cu2*(aq) + 2 e → Cu(s) 0.337 Cu2*(aq) + e" – Cu"(aq) 0.153 S(s) + 2 H*(aq) + 2 e → H2S(aq) 0.14 2 H*(aq) + 2 e → H2(g) 0.0000 Pb2*(aq) + 2 e → Pb(s) -0.126 Sn-"(aq) + 2 e¯ → Sn(s) „2+ -0.14 Ni2+(ag) + 2 e →Ni(s) -0.25 Co2+(ag) + 2 e →Co(s) -0.28 Cd2*(aq) + 2 e →Cd(s) -0.403 Cr3+ C* (aq) (aq) + e -0.41 Fe2*(aq) + 2 e →Fe(s) -0.44 Cr3+ (aq) + 3 e → Cr(s) -0.74 Zn2*(aq) + 2 e →Zn(s) -0.763 2 H20(1) + 2 e → H2(g) + 2 OH (aq) -0.83 Mn-"(aq) + 2 e¯ → Mn(s) 2+ -1.18 Als*(aq) + 3 e → Al(s) -1.66 2+ Mg"(aq) + 2 e →Mg(s) -2.37 Na"(aq) + e –→ Na(s) -2.714 K(aq) + e→ K(s) -2.925 Li*(aq) + e Li(s) -3.045
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 3 images

Blurred answer
Knowledge Booster
Electroanalytical Techniques
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY