AQA A-Level Chemistry: Required Practical Activity 5 - Distillation

Overview

• Focus: Separating an organic product from its reaction mixture using distillation.
• Typically asked as a six-mark question in exams.
• Importance: Understanding the method and correcting poorly set up apparatus.

Distillation Process

Purpose

• Separate butanone from a reaction mixture.
• Butanone has a lower boiling point than the secondary alcohol (due to weaker Van Der Waals interactions vs. hydrogen bonds in alcohol).

Apparatus Setup

1. Round Bottom Flask

   • Must have a side arm to attach a Liebig condenser.
   • Add anti-bumping granules:
     • Prevents bumping by ensuring formation of small bubbles.

2. Heating

   • Use an electric heater (safer than a Bunsen burner due to flammable alcohols).

3. Thermometer and Bung

   • Insert thermometer in a bung.
   • Position: Just at the junction with the side arm.
   • Purpose: Measure the temperature of gas as it boils off.
   • Ensure the bung provides a full seal.

4. Liebig Condenser

   • Attach to the side arm.
   • Water flow: Enter at the bottom, exit at the top:
     • Ensures condenser fills with cold water.
     • Incorrect setup may lead to insufficient condensation.

Execution

• Apply heat using the electric heater.
• Collect the distillate when the temperature reaches the boiling point of butanone.

Practical Tips

• Distinguish between distillation and reflux processes.
• Watch for common errors (e.g., incorrect condenser setup).

Conclusion

• This is part of a video series on AQA required practicals.
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