1. 1
   A laboratory technician reacts a sample of ethanoic acid with solid sodium carbonate and observes the products formed.

   (a)

   Which functional group is present in all carboxylic acids, including ethanoic acid?

   [1 mark]

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

   (b)

   Which gas is produced when a carboxylic acid reacts with a carbonate?

   [1 mark]

   • AHydrogen
   • BOxygen
   • CCarbon dioxide
   • DChlorine

   (c)

   State the names of the first three members of the carboxylic acid homologous series.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A student compares the pH of aqueous ethanoic acid with aqueous hydrochloric acid at the same concentration, and investigates what happens when ethanoic acid reacts with an alcohol.

   (a)

   A student compares aqueous ethanoic acid with aqueous hydrochloric acid at the same concentration. Why does the ethanoic acid solution have a higher pH than the hydrochloric acid solution?

   [1 mark]

   • AEthanoic acid does not ionise completely in water, whereas hydrochloric acid does
   • BEthanoic acid contains no hydrogen atoms
   • CHydrochloric acid is not an acid at all
   • DEthanoic acid reacts with itself to form a neutral salt

   (b)

   What type of compound is formed when a carboxylic acid reacts with an alcohol in the presence of an acid catalyst?

   [1 mark]

   • AAn alkene
   • BAn alkane
   • CA polymer
   • DAn ester

   (c)

   Explain what is meant by describing carboxylic acids such as ethanoic acid as 'weak acids'.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A student carries out a series of reactions using ethanoic acid, including reacting it with sodium carbonate and with an alcohol, in order to write balanced equations for each reaction.

   (a)

   Describe what happens when a carboxylic acid, such as ethanoic acid, reacts with a metal carbonate, such as sodium carbonate, and write a word equation for this reaction.

   [3 marks]

   (b)

   Explain why carboxylic acids are described as weak acids, and describe what happens when ethanoic acid reacts with an alcohol in the presence of an acid catalyst.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A chemistry teacher is preparing a revision lesson on the properties and reactions of carboxylic acids, focusing on ethanoic acid as the main example.

   (a)

   Describe, in detail, the properties of carboxylic acids, including their acidity, their reaction with carbonates, and their reaction with alcohols, and explain why they are described as weak acids.

   [6 marks]

   (b)

   Explain how balanced chemical equations can be used to represent the reactions of carboxylic acids, using the reaction of ethanoic acid with a carbonate and with an alcohol as examples.

   [6 marks]

   Total for question 4: 12 marks

End of questions