Estimation of Sulphur
- Heating a known mass, (m) g, of the organic compound containing sulphur with fuming nitric acid or sodium peroxide in a hard glass tube known as Carius tube in a furnace.
- Sulphur present in the compound is oxidized to sulphuric acid.
- When excess of barium chloride solution in water is added to it, sulphuric acid is precipitated as barium sulphate which is filtered, washed, dried and weighed.
- If mass of (ce{BaSO4}) formed = (m_1), mass of (sulphur) present in it = $$ frac{text {mass of Sulphur in one mole of Barium Sulphate, i.e. 32} }{text{molar mass of Barium Sulphate, i.e. 233}} times m_1 $$ Let it be, (m_2) g
- Mass % = ({m_2 over m} times 100)%
