How is sulphur estimated in a given organic compound ?

Explanation

Estimation of sulphur : The given organic compound is heated with sodium peroxide in the Carius tube. It oxidises the sulphur into sulphuric acid. It is then preciptated as barium sulphate with excess of barium chloride. Then, the precipitate is filtered, dried and weighed. The % age of sulphur can be obtained from the mass of `BaSO_4`
Solutions :
Let the mass of organic compound = mg
Mass of `BaSO_4` formed = `m_1 g`
1 mol of `BaSO_4 = 233 g `of `BaSO_4 = 32 g `sulphur
`[Ba = 137, S = 32,O_4 = 64]`
` m_1 g` of `BaSO_4` contains = `(32 xx m_1)/(233) g`sulphur
Hence, % age of sulphur = `(32 xx m_1 xx 100)/(233 xx m) %` .