Thiosulphate reacts differently with iodine and bromine in the reactions given below: 2 S_2 O_3^2-+ I_2 → S_4 O_6^2-+2 I^- S_2 O_3^2-+5 Br_2+5 H_2 O…

Thiosulphate reacts differently with iodine and bromine in the reactions given below: $$\begin{aligned} & 2 \mathrm{~S}_2 \mathrm{O}_3^{2-}+\mathrm{I}_2 \rightarrow \mathrm{~S}_4 \mathrm{O}_6^{2-}+2 \mathrm{I}^{-} \\ & \mathrm{S}_2 \mathrm{O}_3^{2-}+5 \mathrm{Br}_2+5 \mathrm{H}_2 \mathrm{O} \rightarrow 2 \mathrm{SO}_4^{2-}+4 \mathrm{Br}^{-}+10 \mathrm{H}^{+} \end{aligned} $$ Which of the following statement justifies the above dual behaviour of thiosulphate?