The most stable oxidized species among the following is: 
\(E_{{\mathrm{Cr}_2 \mathrm{O}_7^2}/ \mathrm{Cr}^{3+}}^{o} =1.33 \mathrm{~V} ; E_{\mathrm{Cl}_2 / \mathrm{Cl}^{-}}^{o}=1.36 \mathrm{~V} \)
\( E_{\mathrm{MnO_{4}}^{-} / \mathrm{Mn}^{2+}}^{o}=1.51 \mathrm{~V} ; E_{\mathrm{Cr}^{3+} / \mathrm{Cr}}^{o}=-0.74 \mathrm{~V}\)

1. Cr3+  2. MnO4-
3. Cr2O72- 4. Mn2+ 
Subtopic:  Electrochemical Series |
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The standard reduction potential of Zn2+/Zn  and Cu2+/Cu  is -0.76 and +0.34 V respectively. The oxidising agent and reducing agent, respectively, are 
1. Cu & Zn2+ 2. Zn & Cu
3. Cu2+ & Zn2+ 4. Cu2+ & Zn
Subtopic:  Electrochemical Series |
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Given below are two statements: 

Assertion (A): Cu is less reactive than hydrogen.
Reason (R):  Cu2+/ Cu is negative.
 
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:  Electrochemical Series |
 68%
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