The standard electrode potential (\(E^°\)) for the half-cell reaction \(Fe^{3+} + e^- \rightarrow Fe^{2+}\) at 298 K is :
(Given: \(E^°(Fe^{3+}/Fe) = -0.04\) V and \(E^°(Fe^{2+}/Fe) = -0.44\) V at 298 K)
1. +0.92 V 2. +0.40 V
3. +0.76 V 4. -0.48 V
Subtopic:  Electrode & Electrode Potential |
Level 3: 35%-60%
NEET - 2026
Please attempt this question first.
Hints
Please attempt this question first.

The correct value of cell potential in volts for the reaction that occurs when the following two half cells are connected, is:
\(\mathrm{{Fe}_{ {(aq) }}^{2+}+2 {e}^{-} \rightarrow {Fe}({s}), {E}^{\circ}=-0.44{~V} }\)
\( \mathrm{{Cr}_2 {O}_7^{2-}{ }_{ {(aq) }}+14 {H}^{+}+6 e^{-} \rightarrow 2 {Cr}^{3+}+7 {H}_2 {O}},\)
\( \mathrm{{E}^{\circ}=+1.33 {~V}}\)
1. +1.77 V
2. +2.65 V 
3. +0.01 V 
4. +0.89 V
Subtopic:  Electrode & Electrode Potential |
 75%
Level 2: 60%+
NEET - 2023
Hints

Given below are half-cell reactions:
\(\text{MnO}_{4}^{-}+8 \text{H}^{+}+5 \text{e}^{-} \rightarrow \text{Mn}^{2+}+4 \text{H}_{2} \text{O}, \)
\( \text{E}_{\text{Mn}^{2+}}^{\circ} / \text{MnO}_{4}^{-}=-1.510 \text{ V} \)
\( \frac{1}{2} \text{O}_{2}+2 \text{H}^{+}+2 \text{e}^{-} \rightarrow \text{H}_{2} \text{O}, \)
\( \text{E}_{\text{O}_{2} / \text{H}_{2} \text{O}}^{\circ}=+1.223 \text{ V}\)
Will the permanganate ion, \(\text{MnO}_{4}^{-}\) , liberate \(\text{O}_{2}\) from water in the presence of an acid?

1. No, because \(\text{E}_{\text {cell }}^{\circ}=-2.733 \text{ V}\)
2. Yes, because \(\text{E}_{\text {cell }}^{\circ}=+0.287 \text{ V}\)
3. No, because \(\text{E}_{\text {cell }}^{\circ}=-0.287 \text{ V}\)
4. Yes, because \(\text{E}_{\text {cell }}^{\circ}=+2.733 \text{ V}\)
Subtopic:  Electrode & Electrode Potential |
Level 3: 35%-60%
NEET - 2022
Hints

advertisementadvertisement

Two half cell reactions are given below:
\(\begin{aligned} &\mathrm{{Co}^{3+}+e^{-} \rightarrow {Co}^{2+}, {E}_{{Co}^{2+} / {Co}^{3+}}^{\circ}=-1.81 {~V}} \\ &2 \mathrm{{Al}^{3+}+6 e^{-} \rightarrow 2 {Al}({s}), {E}_{{Al} / {Al}^{3+}}^{\circ}=+1.66 {~V}} \end{aligned} \)
The standard EMF of a cell with feasible redox reaction will be:

1. +7.09 V 2. +0.15 V
3. +3.47 V 4. –3.47 V
Subtopic:  Electrode & Electrode Potential |
 69%
Level 2: 60%+
NEET - 2022
Hints

Consider the change in oxidation state of bromine corresponding to different emf values as shown in the diagram below: 
 

The species undergoing disproportionation is:

1. \(\text{BrO}^-_3\) 2. \(\text{BrO}^-_4\)
3. \(\text{Br}_2\) 4. \(\text{HBrO}\)
Subtopic:  Electrode & Electrode Potential |
 62%
Level 2: 60%+
NEET - 2018
Hints

Consider the given cell:
\(\mathrm{Z n   \left|\right. Z n S O_{4}   \left(\right. 0 . 01   M \left.\right)   \left|\right. \left|\right.   C u S O_{4} \left(\right. 1 . 0   M \left.\right)   \left|\right.   C u}\)
In the electrochemical cell, the emf of this Daniel cell is E1. When the concentration of ZnSO4 is changed to 1.0 M and that of CuSO4 is changed to 0.01 M, the emf changes to E2. From the following, which one is the relationship between E1 and E2 ?

(Given: \(\frac{RT}{F}\) = 0.059)

1. \(\mathrm{E_{1} < E_{2}}\) 2. \(\mathrm{E_{1} > E_{2}}\)
3. \(\mathrm{E_{2} = 0 \neq E_{1}}\) 4. \(\mathrm{E_{1} = E_{2}}\)
Subtopic:  Electrode & Electrode Potential | Nernst Equation |
 71%
Level 2: 60%+
NEET - 2017
Hints

advertisementadvertisement

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
Hints
Links

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
Hints

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
Hints
Links

advertisementadvertisement

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
Hints