Question

Use the data given below and find out the most stable oxidised species.

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

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

• A. $Cr^{3 +}$
• B. $MnO_{4}^{-}$
• C. $Cr_{2}O_{7}^{2 -}$
• D. $Mn^{2 +}$

Answer 1

Answer: (A)

$Cr^{3 +}$

Answer 2

$Eº_{Cr^{3 +}/Cr}$ has lowest reduction potential hence, $Cr^{3 +}$is the most stable oxidized species.