Balance the following redox reactions by ion – electron method:

(in acidic solution)

Following the steps as in part (A), we have the oxidation half reaction as:-


SO2(g) + 2H2O(l)→ HSO-4(aq) + 3H+(aq) + 2e-(aq)


And the reduction half reaction as:


MnO-4(aq) + 8H+(aq) + 5e-→ Mn2+(aq) + 4H2O


Multiplying the oxidation half reaction by 5 and the reduction half reaction by 2, and then by adding them, we have the net balanced redox reaction equation as:


2MnO-4(aq) + 5SO2(g) + 2H2O + H+(aq)→ Mn2+(aq) + 5HSO-4(aq)


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