Standard reduction potentials of the half-reactions are given below: 

F2(g) + 2e-2F-(aq) ; E° =+2.85 V 

Cl2(g) + 2e-2Cl-(aq) ; E° =+1.36 V 

Br2(g) + 2e-2Br-(aq) ; E° =+1.06 V 

I2(g) + e-2I-(aq) ; E° =+0.53 V 

The strongest oxidizing and reducing agents, respectively, are: 

1. Br2 and Cl-

2. Cl2 and Br-

3. Cl2 and I2

4. F2 and l-

Subtopic:  Emf & Electrode Potential |
 85%
Level 1: 80%+
AIPMT - 2012
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The Mn3+ ion is unstable in solution and undergoes disproportionation reaction to give Mn2+, MnO2 and H+ ion. The balanced ionic equation for the reaction is-

1. \(2 \mathrm{Mn}^{3+}{ }_{(\mathrm{aq})}+2 \mathrm{H}_2 \mathrm{O}_{(\mathrm{l})}\)\({\mathrm{MnO}_{2(\mathrm{~s})}+\mathrm{Mn}^{2+}{ }_{(\mathrm{aq})}+4 \mathrm{H}^{+}{ }_{(\mathrm{aq})}}\)
2. \( \mathrm{Mn^{3+}_{(aq)} + H_2O_{(l)} } \)\({\mathrm{MnO}_{2(\mathrm{~s})}+\mathrm{2Mn}^{2+}{ }_{(\mathrm{aq})}+4 \mathrm{H}^{+}{ }_{(\mathrm{aq})}}\)
3. \(5 \mathrm{Mn}^{3+}(\mathrm{aq})+2 \mathrm{H}_2 \mathrm{O}_{(\mathrm{l})}\)\(\mathrm{MnO}_{2(\mathrm{s})}+3 \mathrm{Mn}^{2+}(\mathrm{aq})+4 \mathrm{H}^{+}(\mathrm{aq})\)
4. \(2 \mathrm{Mn}^{3+}{ }_{(\mathrm{aq})}+2 \mathrm{H}_2 \mathrm{O}_{(\mathrm{l})} \)\(2 \mathrm{MnO}_{2(\mathrm{s})}+2 \mathrm{Mn}^{2+}{ }_{(\mathrm{aq})}+4 \mathrm{H}^{+}{ }_{(\mathrm{aq})}\)

Subtopic:  Emf & Electrode Potential |
 82%
Level 1: 80%+
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Which of the following is the strongest oxidising agent?

1. BrO3/Br2+,Eo=+1.50

2. Fe3+/Fe2+,Eo=+0.76

3. MnO4/Mn2+,Eo=+1.52

4. Cr2O72/Cr3+,Eo=+1.33

Subtopic:  Emf & Electrode Potential |
 81%
Level 1: 80%+
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The correct statement about the given reaction is-

(CN)2(g) + 2OH-(aq) CN-(aq) + CNO-(aq) + H2O(l)

1. The reaction is an example of a disproportionation reaction.
2. Hydrogen atom gets oxidized.
3. Reaction occurs in acidic medium.
4. None of the above

Subtopic:  Emf & Electrode Potential |
 83%
Level 1: 80%+
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The standard electrode potential (E°) values of  Al3+/ Al,  Ag+ / Ag, K+ / K,  and Cr3+ / Cr are –1.66 V, 0.80 V, –2.93 V, & –0.79 V respectively. The correct decreasing order of the reducing power of the metal is:

1. Ag > Cr > Al > K 2. K > Al > Cr > Ag
3. K > Al > Ag > Cr 4. Al > K > Ag > Cr
Subtopic:  Emf & Electrode Potential |
 73%
Level 2: 60%+
NEET - 2019
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(a) \(E_{k^+/K}^o = - 2.93\ V\); \(E_{Ag^+/Ag}^o = 0.80\ V\)
(b) \(E_{Hg^{2+}/Hg}^o = 0.79\ V\); \(E_{Mg^{2+}/Mg}^o = - 2.37\ V\)  
(c) \(E_{Cr^{3+}/Cr}^o = -0.74\ V\)

Based on standard electrode potentials given above, the correct arrangement for increasing order of reducing power of
elements is: 

1. \(\mathrm{Ag}<\mathrm{Hg}<\mathrm{Cr}<\mathrm{Mg}<\mathrm{K} \)
2. \(\mathrm{Ag}>\mathrm{Cr}>\mathrm{Mg}>\mathrm{Hg}>\mathrm{K}\)
3. \(\mathrm{K}>\mathrm{Mg}<\mathrm{Cr}<\mathrm{Hg}>\mathrm{Ag} \)
4. \(\mathrm{K}<\mathrm{Mg}<\mathrm{Cr}<\mathrm{Hg}<\mathrm{Ag}\)
Subtopic:  Emf & Electrode Potential |
 76%
Level 2: 60%+
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The correct statement about electrolysis of an aqueous solution of CuCl2 with Pt electrode is-

1. Cu2+  ion reduced at the cathode;  Cl-  ion oxidized at the anode 
2. Cu2+  ion reduced at the anode;  Cl-  ion oxidized at the cathode
3. Cu2+  ion reduced at the cathode;  H2O  ion oxidized at the anode 
4. H2O  ion reduced at the cathode;  Cl-  ion oxidized at the anode 

Subtopic:  Emf & Electrode Potential |
 68%
Level 2: 60%+
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EΘ values of some redox couples are given below. On the basis of these values choose the correct option.

EΘvalues:Br2/Br-=+1.90
Ag+/Ag(s)=+0.80
Cu2+/Cu(s)=+0.34;
I2(s)/I-=+0.54

1. Cu will reduce Br 2. Cu will reduce Ag
3. Cu will reduce I 4. Cu will reduce Br2
Subtopic:  Emf & Electrode Potential |
 61%
Level 2: 60%+
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The correct statement about the electrolysis of an aqueous solution of AgNO3 with Pt electrode is:
 

1. Pt(s) gets oxidized at cathode whereas  Ag + ( aq )  gets reduced at anode
2. Ag+ (aq)  gets reduced at cathode and is oxidized at anode
3. Ag+ (aq) gets reduced at cathode whereas water is oxidized at anode
4. Ag (s) gets oxidized at cathode whereas  H2O  is oxidised at anode

Subtopic:  Emf & Electrode Potential |
 65%
Level 2: 60%+
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A solution contains Fe2+, Fe3+ and I ions. This solution was treated with iodine at 35°C. E° for Fe3+/Fe2+ is +0.77 V and E° for I2/2I = 0.536 V.
The favourable redox reaction is:

1. Fe2+ will be oxidized to Fe3+.

2. I2 will be reduced to I.

3. There will be no redox reaction.

4. I will be oxidized to I2.

Subtopic:  Emf & Electrode Potential |
 54%
Level 3: 35%-60%
AIPMT - 2011
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