In the sulphur estimation, 0.20 g of a pure organic compound gave 0.40 g of barium sulphate. The percentage of sulphur in the compound is 10-1\%. (Molar mass : O = 16, S = 32, Ba = 137 in g mol-1)
Answer
275
Solution
Carius method: all S of the compound goes to BaSO4.
S fuming HNO3, H2SO4 BaCl2BaSO4 (233 g contains 32 g S)
\% S= 32233 0.400.20 100
=27.47\%=274.7 10-1\%
275 (nearest integer)
Answer: 275