In the estimation of sulphur by Carius method, 0.468g of an organic sulphur compound afforded 0.668g of barium sulphate. Find out the percentage of sulphur in the given compound.
(Ba= 137, S=32, O=16)

Explanation

molar mass of `BaSO_(4)= 137 + 32 (16 xx 4)= 233g`
`underset(32g)(S) rarr underset(233g)(BaSO_(4))` contain 32g sulphur,
`:. 0.668g BaSO_(4)` contain
Sulphur `= (32 xx 0.668)/(233) gm`
% `S = (32)/(233) xx (0.668)/(0.468) xx 100` = 19.60%