Practical 10b

• Outline a method for the production of ethyl ethanoate from ethanol and ethanoic acid.

  > Mix 10 cm3 of ethanol and 10 cm3 ethanoic acid in a round bottom flask

  > Add a few drops of concentrated sulfuric acid whilst swirling. Ensure the round bottom flask is cooled with water and ice

  > Reflux the mixture for 15 minutes

  > Transfer the mixture into a beaker containing saturated sodium carbonate to neutralise the acids. There will be lots of fizzing
• Outline a method for the production of ethyl ethanoate from ethanol and ethanoic acid.

  > Transfer the mixture into a separating funnel, invert and allow the gas to escape. Repeat until two layers form

  > Discard the aqueous layer and keep the upper organic layer

  > Add excess drying agent i.e. anhydrous sodium sulfate to the organic layer to absorb any remaining water

  > Filter the mixture to collect the dry ethyl ethanoate

  > Use distillation to purify the ethyl ethanoate. Compare the temperature the distillate is collected to a data book
• Why is the mixture added to a saturated sodium carbonate solution?

  To neutralise all the acids
• Why does the tap of the separating funnel need to be opened frequently when shaking the mixture with the saturated sodium carbonate solution?

  To allow the gas to escape and prevent the build-up of pressure
• Why do two layers form in the separating funnel?

  They have different densities and they are immiscible
• The density of ethyl ethanoate is 0.90 g/cm3. In which layer would you expect to find ethyl ethanoate and why?

  The top layer because it is less dense than water ((1.00 g/cm3)
• Why are a few lumps of anhydrous sodium sulfate added to the crude ethyl ethanoate?

  To absorb water
• When excess anhydrous sodium sulfate is added to the crude ethyl ethanoate, an observation is seen. The mixture turns from cloudy to?

  Clear
• Give two properties of a drying agent such as anhydrous sodium sulfate.

  > Absorb water

  > Insoluble
• How is the drying agent removed from the mixture?

  Filtration
• The dry ethyl ethanoate can be further purified. What practical technique could be used to purify the dry ethyl ethanoate?

  Distillation