Which of the following electrodes will act as anodes, when connected to Standard Hydrogen Electrode?
\(\begin{array}{rlr}\text { (a) } & \mathrm{{Al}^{3+} / {Al}} & \mathrm{{E}_{RP}^{o}=-1.66} \\\text { (b) } & \mathrm{{Fe}^{2+} / {Fe}} & \mathrm{{E}_{RP}^{o}=-0.44} \\\text { (c) } & \mathrm{{Cu}^{2+} / {Cu}} & \mathrm{{E}_{RP}^{o}=+0.34} \\\text { (d) } & \mathrm{{F}_{2}({~g}) / 2 {~F}^{-}({aq})} & \mathrm{{E}_{RP}^{o}=+2.87}\end{array}\)

   
The correct choice among the above is:

1. (a, b)

2. (b, c)

3. (c, d)

4. (a, d)

Subtopic:  Emf & Electrode Potential |
 70%
Level 2: 60%+
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The reducing ability of the metals K, Au, Zn, and Pb follows the order

1. K > Pb > Au > Zn 2. Pb > K > Zn > Au
3. Zn > Au > K > Pb 4. K > Zn > Pb > Au
Subtopic:  Application of Electrode Potential | Emf & Electrode Potential |
 80%
Level 1: 80%+
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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 |
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Level 2: 60%+
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Given below are two statements: 
Assertion (A): Among halogens, fluorine is the best oxidant.
Reason (R): Fluorine is the most electronegative atom.
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. (A) is False but (R) is True.
Subtopic:  Emf & Electrode Potential |
Level 3: 35%-60%
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Under standard conditions ,the reactions that is/are spontaneous:
Half-Reaction Eº(V)
Cu+(aq) + e¯ → Cu(s) +0.52
Co2+(aq) + 2 e¯ → Co(s) –0.28
In3+(aq) + 3 e¯ → In(s) –0.34
I.  2 Cu+(aq) + Co(s) → Co2+(aq) + 2 Cu(s)
II. 3 Co2+(aq) + 2 In(s) → 2 In3+(aq) + 3 Co(s)
1. I only 2. II only
3. Both I and II 4. Neither I nor II
Subtopic:  Emf & Electrode Potential |
 65%
Level 2: 60%+
Please attempt this question first.
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Please attempt this question first.

At \(298 {~K},\) the standard electrode potentials of \(\mathrm{{Cu}^{2+} /{Cu},}\) \(\mathrm{{Zn}^{2+} / {Zn},~~ {Fe}^{2+} / {Fe}}\) and \(\mathrm{{Ag}^{+} / {Ag}} \) are \(\mathrm{0.34 {~V}, -0.76 {~V},}\)  \(\mathrm{-0.44 {~V}}\) and \(\mathrm{0.80 {~V},}\) respectively.
On the basis of standard electrode potentials, predict which of the following reaction can not occur?
1. \(\mathrm{2 {CuSO}_{4}({aq})+2 {Ag}({s}) → 2 {Cu}({s})+{Ag}_{2} {SO}_{4}({aq})} \)
2. \(\mathrm{{CuSO}_{4}({aq})+{Zn}({s})} \) \(\mathrm{→ {ZnSO}_{4}({aq})+{Cu}({s})} \)
3. \(\mathrm{{CuSO}_{4}({aq})+{Fe}({s})} \) \(\mathrm{→ {FeSO}_{4}({aq})+{Cu}({s})} \)
4. \(\mathrm{{FeSO}_{4}({aq})+{Zn}({s})} \) \(→ \mathrm{{ZnSO}_{4}({aq})+{Fe}({s})} \)
Subtopic:  Emf & Electrode Potential |
 69%
Level 2: 60%+
NEET - 2022
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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 |
 83%
Level 1: 80%+
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Consider the standard electrode potentials given below:
(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) \(E_{Cr^{3+}/Cr}^o = -0.74\ V\)


The correct arrangement of increasing order for 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 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 metals 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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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 |
 69%
Level 2: 60%+
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