Fractional distillation

• What is the purpose of fractional distillation?


  To separate a mixture of liquids
• How does fractional distillation work in a lab demonstration?


  A mixture is heated in a flask with a fractionating column on top
• What happens to liquids with different boiling points during fractional distillation?


  They evaporate at different temperatures
• Which liquid evaporates first during fractional distillation?


  The liquid with the lowest boiling point
• What occurs when the temperature on the thermometer matches the boiling point of a liquid?


  The liquid reaches the top of the column
• Why do liquids with higher boiling points not reach the top of the column?


  Because the column is cooler towards the top, causing them to condense
• What should you do after collecting the first liquid in fractional distillation?


  Raise the temperature until the next liquid reaches the top
• What is the process of fractional distillation in a refinery for crude oil?


  1. Mixture of liquids is placed in a flask
  2. Fractionating column is attached and heated
  3. Liquids evaporate at different temperatures based on boiling points
  4. Lowest boiling point liquid evaporates first
  5. Higher boiling point liquids condense and return to the flask
  6. Temperature is raised to collect the next liquid
• What are the boiling points of propan-1-ol, methanol, and ethanol?


  Propan-1-ol: 97 °C, Methanol: 65 °C, Ethanol: 78 °C
• Which liquid will be collected in the second fraction when separating propan-1-ol, methanol, and ethanol?


  Ethanol, because it has the second lowest boiling point
• Why is it important to scribble down the information about separation techniques?


  To ensure you remember and understand the techniques for exams
• What is the significance of the fractionating column in fractional distillation?


  • Allows separation of liquids based on boiling points
  • Cooler at the top to facilitate condensation of higher boiling point liquids
  • Essential for effective distillation process
• What method is used to separate a mixture of liquids?

  Fractional Distillation
• What is the purpose of a fractionating column in fractional distillation?

  • To separate liquids based on boiling points
  • Contains glass rods to facilitate condensation
  • Cooler at the top to allow higher boiling point liquids to condense
• What happens to the liquid with the lowest boiling point during fractional distillation?


  It evaporates first and reaches the top of the column when the thermometer matches its boiling point.
• Why do liquids with higher boiling points not reach the top of the fractionating column?


  Because the column is cooler towards the top, causing them to condense and run back down.
• What should you do after collecting the first liquid in fractional distillation?


  Raise the temperature until the next liquid reaches the top.
• What are the boiling points of propan-1-ol, methanol, and ethanol?


  • Methanol: 65 °C
  • Ethanol: 78 °C
  • Propan-1-ol: 97 °C
• Which liquid will be collected in the second fraction when separating a mixture of propan-1-ol, methanol, and ethanol?


  Ethanol will be collected second because it has the next lowest boiling point after methanol.
• Why is it important to scribble down the techniques learned in fractional distillation?


  To ensure understanding and retention of the separation techniques.
• What is the significance of the temperature on the thermometer during fractional distillation?


  • Indicates the boiling point of the liquid being collected
  • Helps in determining when to collect the next fraction
  • Essential for monitoring the separation process