Question 42
Sulphur and its CompoundsA rock sample was added to cold dilute HNO3. The gas evolved was passed into a solution of acidified K2Cr2O7 and the solution turned green. The rock sample contains
- A.Cl−
- B.NO3−
- C.SO32−
- D.SO42−
Show the answer and explanation
Answer: C (SO32−)
Explanation
A trioxosulphate (IV) (SO32−) gives SO2 with dilute acid, and SO2 turns orange acidified dichromate green.