Acidified potassium dichromate oxidizes sulphides ($S^{2-}$) to............
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → sulphur (S)
- Acidified potassium dichromate ($K_2Cr_2O_7/H^+$) is a strong oxidizing agent.
- When it reacts with sulfide ions (S²⁻), it oxidizes them to elemental sulfur:
- Further oxidation to $SO_2$ or $SO_4^{2-}$ requires stronger conditions.
Hence, the product is Sulfur (S).