Question

In the estimation of sulphur by Carius method, 0.468 g of an organic sulphur compound afforded 0.668 g of barium sulphate. Find out the percentage of sulphur in the given compound.

Answer 1

The molar mass of $BaS{O}_4$ is 233 g/mol.
Thus, 233 g of $BaS{O}_4$ corresponds to 32 g of sulphur.
0.668 g of $BaS{O}_4$ will contain $\frac{32\times 0.668}{233}=0.0917g$ of sulphur.
The percentage of sulphur in the given compound is $\frac{0.0917\times 100}{0.468}=19.6$ %.