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+ |
1. | Cu & Zn2+ | 2. | Zn & Cu |
3. | Cu2+ & Zn2+ | 4. | Cu2+ & Zn |
Given below are two statements:
Assertion (A): | Cu is less reactive than hydrogen. |
Reason (R): | E°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. |