Experiment 5: Fractional Distillaion of a Hydrocarbon Mixture

1. Construct a fractional distillation apparatus

2. Separate components of a mixture using fractional distillation

3. Identify components by their boiling points

Objectives for this experiment

Petroleum

Primarily a mixture of hydrocarbons

Separate the components of the hydrocarbon mixture

Crucial step in order to refine petroleum

20^o C and 400^o C

Boiling points of pure hydrocarbons

Boiling points

Reason why it is possible to separate petroleum intro smaller groups of hydrocarbons

Fractional distillation

Involves the use of fractionating column in a distillation apparatus

Provide greater purity by letting the component with the lower boiling point to reach the condenser

Purpose of the fractionating column

Between the initial mixture and the condenser

Where the column is placed in between

Glass or ceramic beads

Materials that allow vapor to condense and vaporize many times as it travels up to the column

Theoretical plate

Each condensation and evaporation cycle

Improved separation between the compounds

What happens with more theoretical plates in the column

Lower yield

What happens when mixture is stuck inside the column on the beads

1. Three 50 mL graduated cylinders

2. Hydrocarbon mixture (acetone/2-butanone)

3. Distillation equipment

4. Boiling chips

5. Vernier LabQuest

6. Vernier temperature probe

7. Heating mantle

8. 25 mL graduated cylinder

9. 10 mL graduated cylinder

Materials used

Toxic

Hazard of hydrocarbon vapors