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NEETChemistryd and f Block Elements

In a faintly alkaline medium, potassium permanganate oxidises thiosulphate quantitatively. What are the oxidation states of sulphur and manganese in the products formed from this reaction?

Options

  1. A+2.5 and +2
  2. B+6 and +4
  3. C+6 and +6
  4. D+4 and +2

Correct answer

B. +6 and +4

Step-by-step solution

In a faintly alkaline medium, potassium permanganate ( KMnO₄ ) oxidises thiosulphate ( S₂O₃²⁻ ) to sulphate ( SO₄²⁻ ), while it gets reduced to manganese dioxide ( MnO₂ ). The chemical equation is: 8MnO₄^- + 3S₂O₃²⁻ + H₂O 8MnO₂ + 6SO₄²⁻ + 2OH^- The oxidation state of sulphur in sulphate ( SO₄²⁻ ) is +6 . The oxidation state of manganese in manganese dioxide ( MnO₂ ) is +4 . Therefore, the oxidation states of sulphur and manganese in the products are +6 and +4 respectively. Answer: +6 and +4

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