Separating Mixture using Sublimation

Separating mixture using sublimation     

Requirements.

1. Sodium chloride.

2. Ammonium chloride.

3.  Bunsen burner.

4. Wire gauze.

5. Watch glass.

6. Beaker.

7. Cold water in a round bottomed flask.

Separating mixture using sublimation

Procedure.

1. Mix sodium chloride (common salt) and ammonium chloride in a glass beaker.

2. Cover the beaker with a round-bottomed flask containing cold water.

3. Heat the mixture gently and observe what happens. Record your observation.

Questions from the experiment.

1. What happens to the mixture when heated?

2. What happens to the surface of the round-bottomed flask?

3. Describe the work of the cold water in the round-bottomed flask.

Observation and explanation.

1. Ammonium chloride form white fumes which condense into a white solid on the cooler surface of the round-bottomed flask and the beaker.

2. Sodium chloride (salt) remains in the beaker.

3. Sublimation is the direct change of a solid into gas after heating and vapour into solid on cooling without passing through the liquid state.

4. A sublimate is the solid formed when a vapour cools.