Question 36
Sulphur and its CompoundsA gas that will turn orange potassium heptaoxodichromate (VI) solution to clear green is
- A.sulphur (VI) oxide
- B.hydrogen sulphide
- C.sulphur (IV) oxide
- D.hydrogen chloride
Show the answer and explanation
Answer: C (sulphur (IV) oxide)
Explanation
SO2 reduces orange dichromate(VI) to green chromium(III), giving a clear green solution. H2S also reduces it but leaves a cloudy yellow deposit of sulphur.