1. 1
   A perfume company uses a range of esters to create the distinctive scents used in its fragrances.

   (a)

   Which functional group is present in all esters?

   [1 mark]

   • A−OH
   • B−COOH
   • C−COO−
   • DC=C

   (b)

   Which property of esters makes them particularly suitable for use in perfumes?

   [1 mark]

   • AThey are volatile compounds with distinctive smells
   • BThey are strong acids
   • CThey conduct electricity well
   • DThey are completely odourless

   (c)

   State two uses of esters.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A laboratory technician prepares a sample of the ester ethyl ethanoate from two simple starting materials, using a catalyst to speed up the reaction.

   (a)

   A laboratory prepares the ester ethyl ethanoate. Which two substances react together to produce this ester?

   [1 mark]

   • AEthanol and sodium carbonate
   • BEthanol and ethanoic acid
   • CEthanoic acid and bromine water
   • DEthene and steam

   (b)

   What type of catalyst is typically used to speed up the reaction between an alcohol and a carboxylic acid to form an ester?

   [1 mark]

   • ABromine
   • BYeast
   • CA metal carbonate
   • DAn acid catalyst

   (c)

   Describe the reaction between ethanol and ethanoic acid that produces ethyl ethanoate.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A food scientist investigates several ester compounds used to create fruity flavourings, and studies how ethyl ethanoate is produced from simpler starting materials.

   (a)

   A chemist is given the name and structural formula of an unknown compound. Explain how the chemist could recognise that the compound is an ester.

   [3 marks]

   (b)

   Describe the properties of esters that make them useful as flavourings, and describe, with a word equation, how ethyl ethanoate is formed.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A cosmetics and food flavouring company relies on a range of esters, including ethyl ethanoate, to give its products distinctive scents and tastes, and wants staff to understand how these compounds are made and identified.

   (a)

   Explain what esters are, how they can be recognised from their name or structural formula, and describe in detail how ethyl ethanoate is formed from ethanol and ethanoic acid.

   [6 marks]

   (b)

   Discuss the uses of esters as flavourings and perfumes, explaining how the properties of esters make them suitable for these applications.

   [6 marks]

   Total for question 4: 12 marks

End of questions