explain how you can obtain pure samples from a mixture containing ammonium chloride,copper(ii)oxide and potassium carbonate
To obtain pure samples from a mixture containing ammonium chloride, copper(II) oxide, and potassium carbonate, you can utilize various separation techniques based on the physical properties of the substances involved. Here's a step-by-step explanation of how to obtain pure samples:
1. Filtration: Start by pouring the mixture into a funnel with filter paper. Since copper(II) oxide is insoluble in water, it will remain on the filter paper, while ammonium chloride and potassium carbonate will pass through as the filtrate. Collect the filtrate in a beaker.
2. Crystallization: Heat the beaker containing the filtrate until the water evaporates, leaving behind solid ammonium chloride crystals. Ammonium chloride has a lower boiling point compared to potassium carbonate, so only ammonium chloride will be left as a residue.
3. Filtration (again): Transfer the remaining solid ammonium chloride into a new beaker. Add water and stir until the ammonium chloride dissolves completely. Then, filter the solution again to remove any insoluble impurities.
4. Evaporation: Carefully heat the filtered ammonium chloride solution in a separate beaker. As the water evaporates, ammonium chloride crystals will form. Allow the solution to cool down to room temperature or place it in a refrigerator to facilitate crystal formation.
5. Collection: Separate the ammonium chloride crystals by filtration and let them air dry. You now have a pure sample of ammonium chloride.
To obtain a pure sample of copper(II) oxide and potassium carbonate, the remaining mixture in the original funnel can be further processed using the following steps:
6. Extraction: Transfer the residue remaining on the filter paper from step 1 into a beaker. Add water and stir to dissolve the copper(II) oxide, as it is soluble in acidified water forming copper sulfate. This will leave behind insoluble potassium carbonate.
7. Filtration (last time!): Filter the solution to separate the insoluble potassium carbonate. Collect the filtrate, which now contains the copper sulfate solution.
8. Crystallization (again): Heat the filtrate containing the copper sulfate solution until the water evaporates completely. This will result in the formation of copper sulfate crystals.
9. Collection: Filter out and air dry the copper sulfate crystals. Now, you have a pure sample of copper(II) sulfate.
By following these steps, you can obtain pure samples of ammonium chloride, copper(II) oxide, and potassium carbonate from the original mixture.