Distillation

• What are the two types of distillation used to separate liquid mixtures?

  Simple distillation and fractional distillation
• What is the purpose of simple distillation?

  To separate a liquid from a solution
• How can simple distillation be used with seawater?

  It can separate pure water from seawater
• What equipment is used in simple distillation?

  A flask, thermometer, condenser, beaker, and heating device
• What is the function of the thermometer in simple distillation?

  To measure the temperature inside the flask
• How does the condenser work in simple distillation?

  It cools and condenses vapor into liquid form
• What happens to the vapor as it passes through the condenser?

  It cools and condenses into liquid form
• What is left in the flask after simple distillation of seawater?

  Salt
• Why can't simple distillation separate liquids with similar boiling points?

  Because more than one liquid will evaporate
• What is the main technique used for separating mixtures of liquids?

  Fractional distillation
• What is the role of the fractionating column in fractional distillation?

  It allows for better separation of liquids with similar boiling points
• How does the height of the fractionating column affect the separation process?

  A taller column is cooler at the top, aiding in separation
• What happens to methanol when heated in fractional distillation?

  It evaporates and rises up the fractionating column
• At what temperature should the mixture be heated to evaporate methanol?

  Around 65 degrees Celsius
• What happens to ethanol and propanol as methanol rises in the fractionating column?

  They condense back into liquid form and fall back into the flask
• What is the next step after collecting methanol in fractional distillation?

  Raise the temperature to around 78 degrees Celsius to evaporate ethanol
• What can be assumed about the contents of the flask after collecting ethanol?

  It contains mostly propanol
• What could be done to ensure that only propanol is collected at the end of fractional distillation?

  Raise the temperature again to boil off the propanol
• What are the steps involved in simple distillation?

  1. Heat the mixture in the flask.
  2. The desired liquid evaporates and rises.
  3. Vapor passes through the condenser.
  4. Vapor cools and condenses into liquid.
  5. Collect the distilled liquid in a beaker.
  6. Residue remains in the flask.
• What are the steps involved in fractional distillation?

  1. Heat the mixture in the flask.
  2. The liquid with the lowest boiling point evaporates first.
  3. Vapor rises through the fractionating column.
  4. Condenses on the glass rods and falls back.
  5. The desired liquid passes into the condenser.
  6. Collect the distilled liquid in a beaker.
  7. Repeat for other liquids by adjusting the temperature.