Answer: We have
The given redox reaction can be represented as:
Cl2(g) + So2(aq) + Cl-(aq) + So42-(aq)
The oxidation half reaction is:
S+4O2(aq) → S+6O42-(aq)
The oxidation number is balanced by adding two electrons as:
So2(aq) → So42-(aq) + 2e-
The charge is balanced by adding 4H+ ions as:
So2(aq) → So42-(aq) + 2e-
The O atoms and H+ ions are balanced by adding 2H2O molecules as:
So2(aq) + 2H2O(I) → sO42-(aq) + 4H+(aq) + 2e- ...............(i)
The reduction half reaction is:
Cl2(g) → Cl-(aq)
The chlorine atoms are balanced as:
Cl02(s) → Cl-1-(aq)
The oxidation number is balanced by adding electrons
Cl2(g) + 2e- → 2Cl-(aq) ............(i)
The balanced chemical equation can be obtained by adding equation (i) and (ii) as:
Cl2(s) + So2(aq) + 2H2O(l) → 2Cl-(aq) + SO42-(aq) + 4H+(aq)