In an estimation of sulphur by Carius method 0.2 g of the substance gave 0.6 g of BaSO4. The percentage of sulphur in the substance is %. (Given molar mass in g mol-1 S : 32, BaSO4 : 233)
Answer
41 or 42
Solution
In Carius method all the sulphur of the compound ends up in BaSO4; 1 mol BaSO4 (233 g) contains 32 g S.
⇒ Mass of S in 0.6 g BaSO4 = 32233 0.6 = 0.0824 g
∴ % S = 0.08240.2 100
= 41.2% ≈ 41
Answer: 41