Balancing redox reactions

Question

Balance the following reaction in neutral medium by oxidation number method only.

S₂O₃²¯ + I₃¯ ---> I¯ + S₄O₆²¯

Answer 1

S₂O₃²¯ + I₃¯ ---> I¯ + S₄O₆²¯

+2..-2....0..-1.....-1...+2.5..-2.....

S: +2 to +2.5 = ∆+0.5 = oxidation

I: 0 to -1 = ∆-1 = reduction (but I₃^- can be viewed as I₂ + I^- so takes 2e- to reduce I₂ to 2I^-)

2S₂O₃^2- ===> S₄O₆^2- + 2e-

I3^- + 2e- ===> 3I^-

2S₂O₃^2- + I3^- ===> S₄O₆^2- + 3I^- ... balanced equation