Application
How do you precipitate barium sulphate?
To precipitate barium sulfate (BaSO4) from a solution containing barium ions (Ba2+) and sulfate ions (SO42-), you typically use a precipitation reaction. This involves adding a suitable reagent to the solution that will react with the ions to form the insoluble barium sulfate precipitate.
Here's the general procedure:
1. Start with a solution containing barium ions (usually as barium chloride or barium nitrate) and sulfate ions (usually as sodium sulfate or ammonium sulfate).
2. Mix the solution thoroughly to ensure even distribution of ions.
3. Add a suitable reagent that will react with the barium ions to form barium sulfate. The most common reagent used is sulfuric acid (H2SO4), which provides sulfate ions. Alternatively, you can use a soluble sulfate salt like sodium sulfate (Na2SO4) or ammonium sulfate ((NH4)2SO4).
4. As you add the reagent, a white precipitate of barium sulfate will form if the concentration of barium ions and sulfate ions is sufficient to exceed the solubility product constant (Ksp) of barium sulfate.
5. Allow the mixture to settle for some time to ensure complete precipitation.
6. Filter the precipitate using filter paper and a funnel to separate it from the liquid (filtrate).
7. Wash the precipitate with distilled water to remove any soluble impurities.
8. Dry the precipitate in an oven or desiccator.
Keep in mind the safety precautions associated with handling barium compounds, as they can be toxic. Ensure proper ventilation and wear appropriate personal protective equipment when working with these chemicals. Additionally, dispose of any waste materials properly according to local regulations.