Question

How are the constituents of gunpowder separated?

Answer 1

Gunpowder is a mixture of sulphur, charcoal and potassium nitrate. When water is added to the mixture, potassium nitrate dissolves. The mixture is then filtered. The filtrate is potassium nitrate solution while the residue is a mixture of sulphur and charcoal. The filtrate is evaporated on a sand bath to obtain potassium nitrate back. When carbon disulphide is added to the residue, sulphur dissolves. When this mixture is filtered the filtrate is sulphur solution while the residue is charcoal. Leaving it open evaporates the sulphur solution. Carbon disulphide then evaporates and sulphur crystals are left behind.