Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
581–590 of 785
Question 581
5 marks · Hard
Answer and see the solution →A solution of ethanoic acid is reacted with calcium carbonate (CaCO₃) powder in a test-tube.
(a)[1 mark]State one observation you would make during the reaction.
(b)[2 marks]Write a balanced symbol equation for the reaction.
(c)[1 mark]Name the salt formed.
(d)[1 mark]Ethanoic acid reacts more slowly than hydrochloric acid of the same concentration. Explain why.
Question 582
2 marks · Hard
Answer and see the solution →Describe two ways you could show that propanoic acid is a weak acid.
Question 583
5 marks · Easy
Answer and see the solution →Methanoic acid is the first member of the carboxylic acid homologous series.
(a)[1 mark]Draw the displayed formula of methanoic acid.
(b)[1 mark]Name the salt formed when methanoic acid reacts with magnesium.
(c)[2 marks]Write a balanced chemical equation for the reaction between methanoic acid and magnesium.
(d)[1 mark]What would you observe during this reaction?
Question 584
5 marks · Easy
Answer and see the solution →Carboxylic acids are weak acids and react with metals to produce salts.
(a)[1 mark]State the name of the unbranched-chain carboxylic acid with four carbon atoms.
(b)[1 mark]Write its molecular formula.
(c)[2 marks]Describe what is meant by a 'weak acid'.
(d)[1 mark]Explain why carboxylic acids react more slowly with magnesium than hydrochloric acid.
Question 585
5 marks · Easy
Answer and see the solution →Vinegar is a dilute solution of ethanoic acid and reacts with sodium carbonate.
(a)[1 mark]State the name and molecular formula of the main acid present in vinegar.
(b)[2 marks]Write a balanced chemical equation for the reaction between ethanoic acid and sodium carbonate.
(c)[2 marks]Calculate the maximum volume of carbon dioxide (in dm³ at room temperature and pressure) produced if 0.1 mol of sodium carbonate reacts completely with excess ethanoic acid.
Question 586
5 marks · Easy
Answer and see the solution →Propanoic acid is a member of the carboxylic acid family.
(a)[1 mark]Draw the displayed formula of propanoic acid.
(b)[2 marks]State why propanoic acid is described as a weak acid.
(c)[2 marks]A piece of magnesium ribbon is added to propanoic acid. What do you expect to observe? Explain your answer.
Question 587
6 marks · Normal
Answer and see the solution →A student is learning about carboxylic acids and how they react with metals.
(a)[1 mark]State the name of the unbranched-chain carboxylic acid with two carbon atoms.
(b)[1 mark]Write the molecular formula for the acid you named in (a).
(c)[2 marks]When this acid reacts with zinc metal, a salt and hydrogen gas are produced.
i. Write a balanced chemical equation (using molecular formulae) for the reaction between the acid from (a) and zinc metal.
(d)[1 mark]Name the salt formed in the reaction in part (c).
(e)[1 mark]Give one observation you would expect when this reaction takes place.
Question 588
6 marks · Normal
Answer and see the solution →A bottle of vinegar is labelled as containing ethanoic acid.
(a)[1 mark]State the name of the main acid found in vinegar.
(b)[2 marks]Explain what is meant by the term 'weak acid', using ethanoic acid as an example.
(c)[2 marks]Vinegar reacts with magnesium metal. Describe the reaction and give one reason why the reaction is slower compared to dilute hydrochloric acid.
(d)[1 mark]State one observation you would make when magnesium reacts with vinegar.
Question 589
6 marks · Normal
Answer and see the solution →A student wants to prepare a sample of sodium butanoate by reacting sodium metal with butanoic acid.
(a)[2 marks]Draw the displayed formula for butanoic acid.
(b)[2 marks]Write a balanced symbol equation (using molecular formulae) for the reaction between sodium metal and butanoic acid.
(c)[2 marks]Calculate the mass of sodium metal required to react completely with 0.10 mol of butanoic acid. (Relative atomic mass: Na = 23)
Question 590
6 marks · Normal
Answer and see the solution →Study the information about the carboxylic acid family and their behaviour as acids.
(a)[2 marks]Give the name and molecular formula of the unbranched-chain carboxylic acid with three carbon atoms.
(b)[2 marks]Explain why carboxylic acids, such as the one named in (a), are described as weak acids.
(c)[2 marks]A student adds magnesium strip to a solution of this acid. The reaction is much slower than when magnesium is added to dilute sulfuric acid. Explain two reasons for this difference.