Question

In a mildly alkaline medium, the thiosulphate ion is oxidised by ${\mathrm{MnO}}_4^{-}$ to "A". The oxidation state of sulphur in "A" is ________.

Answer 1

Solution: In a mildly alkaline medium, thiosulphate will be oxidised into sulphate ions as alkaline are good reducing agents.

The equation will be S₂O₃ ^2- + MnO₄⁻ → SO₄^2- + MnO₂

• Oxidation no. of ‘S’ in SO₄²⁻ is
• x+4(−2)= −2
• x−8=−2
• x=−2+8
• x=6

So, in a mildly alkaline medium, the thiosulphate ion is oxidised by ${\mathrm{MnO}}_4^{-}$ to "A". The oxidation state of sulphur in "A" is +6.