0.316 g of an organic compound, after heating with fuming nitric acid and barium nitrate crystals in a sealed tube gave 0.466 g of the precipitate of barium sulphate. Determine the percentage of sulphur in the compound.
(Atomic masses : Ba = 137, S = 32, O = 16, C = 12, H = 1).

Explanation

Weight of organic compound = 0.32 g
Weight of `BaSO_(4)` formed = 0,466 g
233 g of `BaSO_(4)` contains =32 g of sulphate
`:. "0.466 g of" BaSO_(4) "contain"=(32)/(233) xx 0.466 g "of sulphur"`
`:. "Percentage of sulphur"=(32)/(233) xx (0.466)/(2.32) xx 100=(32)/(233) xx (46.6)/(0.32)=19.999`
% of sulphur= 20%