Q. During a redox titration involving a solution containing ${Fe}^{2 +}$ ions against $MnO_{4}^{-}$ in the presence of excess of $H^{+}$ ions, the number of electrons that gets transferred is
A) 6
B) 5
C) 4
D) 2
Explanation
(b)
${MnO}_{4}^{-} + 8H^{+} + 5e^{-} \longrightarrow {Mn}^{2 +} + 4H_{2}O$
[${Fe}^{2 +} \longrightarrow {Fe}^{3 +} + e^{-}\rbrack$^{5}
[table] ${MnO}_{4}^{-} + 8H^{+} + 5{Fe}^{2 +} \longrightarrow {Mn}^{2 +} + 5{Fe}^{3 +} + 4H_{2}O$ [/table]
$\therefore\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \$Five electrons gets transferred.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.