The correct option is
A 2MnO−4(aq)+5H2O2(aq)+6H+(aq)→2Mn2+(aq)+5O2(g)+8H2O(l)MnO−4(aq)+H2O2(aq)H−→+Mn2+(aq)+O2(g)
(1) First, divide the equation into two halves; an oxidation half-reaction and reduction half- reaction by grouping appropriate species.
MnO−4→Mn2+
H2O2→O2
(2) If necessary, balance both equations by inspection. In doing this ignore any oxygen and hydrogen atoms in the formula units. In other words, balance the non-hydrogen and non-oxygen atoms only.
(3) The third step involves balancing oxygen atoms. To do this, one must use water (H2O) molecules. Use 1 molecule of water for each oxygen atom that needs to be balanced. Add the appropriate number of water molecules to that side of the equation required to balance the oxygen atoms as shown below.
MnO−4→Mn2++4H2O
H2O2→O2
(4) Balancing the hydrogen atoms.
MnO−4+8H+→Mn2++4H2O
H2O2→O2+2H+
(5) The fifth step involves the balancing of positive and negative charges.
[5e−+MnO−4+8H+→Mn2++4H2O]×2
[H2O2→O2+2H++2e−]×5
Now add both the reactions-
2MnO−4(aq)+5H2O2(aq)+6H+(aq)→2Mn2+(aq)+5O2(g)+8H2O(l)