AP EAMCET202124 Aug 2021Morning ShiftChemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Which of the following is not given by SO ₂ ?
Options
- AIt converts acidified iodates to iodine.
- BIt decolourises acidified KMnO ₄ solution.
- CIt reacts with acidified potassium dichromate to form green coloured solution.
- DIt reacts with green coloured ferrous sulphate to form yellowish brown ferric sulphate.
Correct answer
D. It reacts with green coloured ferrous sulphate to form yellowish brown ferric sulphate.
Step-by-step solution
(i) SO ₂ (Sulphur dioxide) reacts with potassium iodate to form sulphuric acid, potassium sulphate and iodine gas. 5 SO ₂+2 KIO ₃+4 H ₂ O 4 H ₂ SO ₄+ K ₂ SO ₄+ I ₂ (ii) 5 SO ₂+2 KMnO ₄+2 H ₂ O K ₂ SO ₄+2 H ₂ SO ₄+2 MnSO ₄ SO ₂ decolourise KMnO ₄ by converting it to Mn ²⁺ (iv) SO ₂ reduces ferric salts into ferrous salt changing colour from yellow to light green. Yellow Fe ₂ ( SO ₄ )₃ + SO ₂+2 H ₂ O Green 2 FeSO ₄ +2 H ₂ SO ₄