Here's how you can separate naphthalene balls from a mixture of sodium chloride using an experiment:
Materials:
* Mixture: Naphthalene balls and sodium chloride
* Beaker: A glass beaker large enough to hold the mixture
* Hot Plate: To heat the mixture (adult supervision required)
* Stirring Rod: To mix the mixture
* Watch Glass: To collect the sublimed naphthalene
* Filter Paper: To filter the sodium chloride solution
* Funnel: To hold the filter paper
* Bunsen Burner: To heat the watch glass (optional)
Procedure:
1. Set up: Place the mixture of naphthalene balls and sodium chloride in the beaker.
2. Heating: Carefully heat the beaker on a hot plate. Naphthalene has a low melting point and will sublimate (transform directly from solid to gas) at a temperature lower than the boiling point of water. The sodium chloride will remain solid.
3. Sublimation: As the naphthalene sublimates, it will vaporize and rise.
4. Condensation: Cover the beaker with the watch glass. The naphthalene vapor will cool and condense on the underside of the watch glass as a solid.
5. Filtering: After the sublimation process, you will be left with solid sodium chloride in the beaker. Pour the remaining mixture into a funnel lined with filter paper. The sodium chloride will be trapped on the filter paper while the water will pass through.
6. Washing: Rinse the solid sodium chloride on the filter paper with distilled water to remove any impurities.
7. Drying: Allow the filter paper and the sodium chloride to air dry.
8. Recovery: The naphthalene can be recovered by scraping it off the watch glass.
Safety Precautions:
* Adult supervision is required for heating the mixture.
* Use a fume hood or well-ventilated area to prevent inhaling naphthalene vapors.
* Wear safety goggles to protect your eyes from any splashes.
Observations:
* You will observe the naphthalene balls disappear from the mixture as they sublimate.
* You will notice white crystals forming on the underside of the watch glass as the naphthalene vapor condenses.
* The remaining mixture will contain only sodium chloride.
Conclusion:
This experiment demonstrates the principle of sublimation and the difference in physical properties between naphthalene and sodium chloride. Sublimation allows us to separate the naphthalene from the mixture, while filtration removes the solid sodium chloride from the water.
