Question

Given

$E_{Cl_{2} / Cl^{-}}^{o}=1.36V, \, E_{Cr^{3 +} / Cr}^{o}= \, -0.74V$

$E_{Cr_{2} O_{7}^{2 -} / Cr^{3 +}}^{o}=1.33V, \, E_{MnO_{4}^{-} / Mn^{2 +}}^{o}=1.51V.$

Among the following, the strongest reducing agent is:

• A. $Mn^{2 +}$
• B. $Cr^{3 +}$
• C. $Cl^{-}$
• D. $Cr$

Answer 1

Answer: (D)

According to the given data standard reduction potential of $Cr$ is lowest. Lower the standard reduction potential, stronger the reducing agent. Therfore $Cr$ is the strongest reducing agent.