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AQA A-Level Chemistry Distillation Guide

Mar 19, 2025

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.
  • Find more revision videos by liking and subscribing to the channel.