Q.
Based on the data given below : $E^\circ_{Cr_2O_7^{2-}/Cr^{3+}}=1.33$ V, $E^\circ_{Cl_2/Cl^-}=1.36$ V, $E^\circ_{MnO_4^-/Mn^{2+}}=1.51$ V, $E^\circ_{Cr^{3+}/Cr}=-0.74$ V, the strongest reducing agent is :
A) Cr
B) $Cl^-$
C) $MnO_4^-$
D) $Mn^{2+}$
Explanation
[Solution by Dr. Abubacker] The strongest reducing agent is the reduced form of the couple with the lowest (most negative) reduction potential. $Cr^{3+}/Cr$ has $-0.74$ V, so $Cr$ is the strongest reductant. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.