Steps:
1. Sample preparation:
Weigh the sample containing barium ions (Ba²⁺) and dissolve in distilled water or dilute HCl.
Filter the solution to remove insoluble impurities.
2. Precipitation:
Add sodium sulfate (Na₂SO₄) to the solution.
Barium ions react with sulfate ions to form Barium Sulphate precipitate:
Ba²⁺ (aq) + SO4²⁻ (aq) → BaSO4 (s)
3. Digestion:
Let the precipitate settle, and optionally heat the solution to improve the precipitate's purity and particle size.
4. Filtration:
Filter the precipitate using suitable filter paper or apparatus.
5. Washing and drying:
Wash the precipitate with distilled water to remove contaminants.
Transfer the precipitate to a pre-weighed crucible and dry in an oven or desiccator.
6. Weighing:
Weigh the dried precipitate and subtract the weight of the empty crucible to obtain the mass of BaSO₄.
7. Calculation:
Calculate the percentage of barium using:
% Ba = (Mass of BaSO4 × Molecular weight of Ba) / (Weight of sample × Molecular weight of BaSO4) × 100