A button cell used in watches functions as following
Zn(s) + Ag2O(s) + H2O(l) \(\rightleftharpoons\) 2Ag(s) + Zn2+(aq) + 2OH(aq)
If half-cell potentials are-
Zn2+(aq) + 2e→ Zn(s)  Eo = – 0.76 V 
Ag2O(s) + H2O(l) + 2e →
2Ag(s) + 2OH(aq)
Eo = 0.34 V

The cell potential will be:

1. 0.42 V 2. 0.84 V
3. 1.34 V 4. 1.10 V
Subtopic:  Electrode & Electrode Potential |
 87%
Level 1: 80%+
AIPMT - 2013
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Consider the half-cell reduction reaction:
\(\text{Mn}^{2+}+2e^-\rightarrow \text{Mn},\ E^{0}= -1.18~ \text V \) 
\(\text{Mn}^{2+}\rightarrow \text{Mn}^{3+}+e^-,\ E^{0}= -1.51~ \text V \)

The \(E^{0}\) for the reaction \(\mathrm{3\ Mn^{2+}\rightarrow Mn^{0}+2Mn^{3+} }\) and possibility of the forward reaction are respectively:
 
1. –4.18 V and Yes 2. +0.33 V and Yes
3. +2.69 V and No 4. –2.69 V and No
Subtopic:  Electrode & Electrode Potential |
 55%
Level 3: 35%-60%
NEET - 2013
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Which of the following represents the correct order of reducing power of metals X, Y, and Z having standard electrode potentials −1.2 V, +0.5 V, and −3.0 V, respectively?
 
1. Y > X > Z 2. Z > X > Y
3. X > Y > Z 4. Y > Z > X
Subtopic:  Electrode & Electrode Potential |
 81%
Level 1: 80%+
AIPMT - 2011
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Based on electrode potentials in the table below: 
Cu2+(aq) + e- → Cu+(aq) 0.15 V
Cu+(aq) + e- → Cu(s) 0.50 V

The value of \(E_{Cu^{2+}/Cu}^{o}\) will be:
1. 0.325 V 2. 0650 V
3. 0.150 V 4. 0.500 V
Subtopic:  Electrode & Electrode Potential |
 63%
Level 2: 60%+
AIPMT - 2011
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What is the standard cell potential when the Sn⁴⁺/Sn²⁺ (E° = +0.15 V) and Cr³⁺/Cr (E° = −0.74 V) half-cells are connected under standard conditions?

1. +0.89 V

2. +0.18 V

3. +1.83 V

4. +1.199 V

Subtopic:  Electrode & Electrode Potential |
 91%
Level 1: 80%+
AIPMT - 2011
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Consider the following relations for emf of an electrochemical cell:

(a) emf of a cell = (Oxidation potential of the anode) – (Reduction potential of the cathode)
(b) emf of a cell = (Oxidation potential of the anode) + (Reduction potential of the cathode)
(c) emf of a cell = (Reduction potential of the anode) + (Reduction potential of the cathode)
(d) emf of a cell = (Oxidation potential of the anode) – (Oxidation potential of the cathode)


Which of the following combinations correctly represents the relation for the emf of the cell?

1. (a) and (b) 2. (c) and (d)
3. (b) and (d) 4. (c) and (a)
Subtopic:  Electrode & Electrode Potential |
 69%
Level 2: 60%+
AIPMT - 2010
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If EFe2+/Feo = -0.441 V and  EFe3+/Fe2+o = 0.771 V, the standard emf of the reaction: 

Fe + 2Fe3+→ 3Fe2+ will be:

1. 0.330 V 2. 1.653 V
3. 1.212 V 4. 0.111 V
Subtopic:  Electrode & Electrode Potential |
 75%
Level 2: 60%+
AIPMT - 2006
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