Starting with barium nitrate solution describe how a pure sample of barium carbonate can be prepared in the laboratory

Answer 1

To prepare a pure sample of barium carbonate (BaCO₃) from barium nitrate (Ba(NO₃)₂), you can follow a double displacement (precipitation) reaction using sodium carbonate (Na₂CO₃) as the reactant. Here is a step-by-step procedure:

Materials Needed:

1. Barium nitrate solution (concentration as desired)
2. Sodium carbonate solution (Na₂CO₃)
3. Distilled water
4. Beakers
5. Stirring rod
6. Filter paper and funnel
7. Ring stand and clamp (if needed)
8. Bunsen burner (optional, for drying the precipitate)
9. Weighing balance (for measuring the dried product)

Procedure:

1. Prepare Solutions:

   • Prepare a barium nitrate solution by dissolving a known amount of barium nitrate in distilled water in a beaker.
   • Prepare a sodium carbonate solution by dissolving a known amount of sodium carbonate in another beaker with distilled water.

2. Mix Solutions:

   • Slowly add the sodium carbonate solution to the barium nitrate solution while continuously stirring the mixture. This will cause a double displacement reaction, which can be represented by the following equation: \[ \text{Ba(NO}_3\text{)}_2(aq) + \text{Na}_2\text{CO}_3(aq) \rightarrow \text{BaCO}_3(s) + 2 \text{NaNO}_3(aq) \]
   • A white precipitate of barium carbonate will form immediately.

3. Allow Precipitate to Settle:

   • Let the mixture sit for a few minutes to allow the barium carbonate precipitate to settle at the bottom of the beaker.

4. Filtering:

   • Set up a filtration apparatus using a funnel and filter paper. Carefully pour the mixture through the filter paper to collect the barium carbonate precipitate. Rinse the precipitate on the filter paper with distilled water to remove any remaining sodium nitrate.

5. Drying:

   • Once the filtration is complete, you can either let the barium carbonate dry at room temperature or use a Bunsen burner to gently heat it until it is fully dry. Be careful not to heat it too strongly to avoid decomposition.

6. Collection:

   • Once dry, scrape the barium carbonate powder from the filter paper and transfer it to a labeled container for storage or further experimentation.

Notes:

• Barium carbonate is insoluble in water, ensuring that the precipitation is effective.
• The purity of the barium carbonate can be confirmed through further analysis, such as X-ray diffraction or spectroscopy, if a high degree of purity is required.
• Handle all chemicals, particularly barium compounds, with appropriate safety measures, including gloves and goggles, and dispose of any waste materials according to local regulations.

By following these steps, you will have successfully prepared a pure sample of barium carbonate from barium nitrate in the laboratory.