Question

Write the balanced oxidation and reduction half reactions for reaction of Fe(II) with permanganate in acidic solution.

Answer 1

Fe2+(aq) + MnO4-(aq) ---> Fe3+(aq) + Mn2+(aq) (acidic solution)

to balance this...
1. Write the half reactions:

Fe2+(aq) ---> Fe3+(aq) (oxidation)

MnO4-(aq) ---> Mn2+(aq) (reduction)

2. Balance each half reaction:

Fe2+(aq) ---> Fe3+(aq) + e-

MnO4-(aq) + 8H+(aq) + 5e- ---> Mn2+(aq) + 4H2O

3. Combine the half reactions to give the overall reaction:
5Fe2+(aq) ---> 5Fe3+(aq) + 5e-
MnO4-(aq) + 8H+(aq) + 5e- ---> Mn2+(aq) + 4H2O
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5Fe2+(aq) + MnO4-(aq) + 8H+(aq) ---> 5Fe3+(aq) + Mn2+(aq) + 4H2O