Question

Use the data given below and find out the most stable ion in its reduced form.

$Eº_{CrO_{7}^{2 -}/Cr^{3 +}} = 1.33V;Eº_{Cl_{2}/Cl} = 1.36V$

$Eº_{MnO_{4}^{-}/Mn^{2 +}} = 1.51V;Eº_{Cr^{3 +}/Cr} = - 0.74V$

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

Answer 1

Answer: (D)

$Mn^{2 +}$

Answer 2

$E{º_{MnO_{4}^{-}}}_{|Mn^{2 +}}$ has highest reduction potential hence, $Mn^{2 +}$is the most stable reduced species.