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JEE Main20248 Apr 2024Morning ShiftChemistryRedox ReactionsActual

Thiosulphate reacts differently with iodine and bromine in the reactions given below: ( aligned & 2 ~S ₂ O ₃²⁻+ I ₂ S ₄ O ₆²⁻+2 I ⁻ & S ₂ O ₃²⁻+5 Br ₂+5 H ₂ O 2 SO ₄²⁻+4 Br ⁻+10 H ⁺ aligned ) Which of the following statement justifies the above dual behaviour of thiosulphate?

Options

  1. ABromine is a stronger oxidant than iodine
  2. BThiosulphate undergoes oxidation by bromine and reduction by iodine in these reaction
  3. CBromine is a weaker oxidant than iodine
  4. DBromine undergoes oxidation and iodine undergoes reduction in these reactions

Correct answer

A. Bromine is a stronger oxidant than iodine

Step-by-step solution

In the reaction of S ₂ O ₃ ²⁻ with I ₂ , oxidation state of sulphur changes to +2 to +2.5 In the reaction of S ₂ O ₃ ²⁻ with Br ₂ , oxidation state of sulphur changes from +2 to +6 . Both I ₂ and Br ₂ are oxidant (oxidising agent) and Br ₂ is stronger oxidant than I ₂ .

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