Practical activity

Distillation

It is important in this core practical to use a range of equipment and methods to separate chemical mixtures. This includes the safe use and careful handling of substances, and the safe use of appropriate heating devices.

This outlines one way to carry out the practical. Eye protection must be worn.

Aims

To investigate the composition of inks using simple distillation.

Simple distillation

The equipment and process needed to investigate the composition of inks using simple distillation.Core practical simple distillation

Method

  1. Add a small volume of ink to a flask. Connect the flask to the fractionating column and secure it with a stand, boss and clamp.
  2. Attach a condenser to the top of the fractionating column, connect it to a cold water tap and sink, and secure it over a beaker.
  3. Heat the flask using a Bunsen burner, reducing the flame as necessary to achieve gentle simmering.
  4. Collect a small sample of the distilled solvent, then turn the Bunsen burner off.

Results

1. Describe the appearance of the distilled solvent.

2. If your apparatus included a thermometer at the top of the column, record the maximum temperature reached as the solvent was collected.

Analysis

3. Explain any difference in the appearance of the solvent and ink.

4. If you measured the maximum temperature, compare this to the boiling points of possible solvents. These could include water, ethanol and propanol.

Evaluation

5. Discuss whether you can identify the solvent from the ink.

Hazards, risks and precautions

Evaluate the hazards and the precautions needed to reduce the risk of harm. For example:

HazardPossible harmPossible precaution
Hot apparatusSkin burnsAllow apparatus to cool before touching it
Bunsen burner flameSkin burnsKeep hair and clothes tucked in
Bunsen burner flameFireDo not bring flammable solvents near to the flame
Move on to Test
next