Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
561–570 of 785
Question 561
3 marks · Normal
Answer and see the solution →Vinegar contains ethanoic acid as its main component. A student finds that a 75 g bottle of vinegar contains 3.0 g of pure ethanoic acid.
Calculate the percentage by mass of ethanoic acid in this sample of vinegar. Give your answer to 2 significant figures.
Question 562
2 marks · Hard
Answer and see the solution →A student writes the name 'proponoic acid' for a carboxylic acid with three carbon atoms in a straight chain.
State the correct IUPAC name for this acid. Give one reason for your answer.
Question 563
5 marks · Hard
Answer and see the solution →Vinegar is commonly used in food and cleaning products.
(a)[1 mark]Name the main carboxylic acid found in vinegar.
(b)[1 mark]State its molecular formula.
(c)[1 mark]Draw the displayed formula for this acid.
(d)[1 mark]Suggest one property of this carboxylic acid that makes it useful in cleaning products.
(e)[1 mark]Explain why this acid is classified as a carboxylic acid, referring to its structure.
Question 564
2 marks · Hard
Answer and see the solution →Draw the structural formula for butanoic acid and state the total number of hydrogen atoms in one molecule.
Question 565
1 mark · Easy
Answer and see the solution →State the gas produced when magnesium metal reacts with dilute propanoic acid.
Question 566
3 marks · Easy
Answer and see the solution →Ethanoic acid is a weak acid.
(a)[1 mark]State the colour change seen when blue litmus paper is placed in ethanoic acid.
(b)[2 marks]Explain what is meant by the term "weak acid".
Question 567
2 marks · Easy
Answer and see the solution →A student reacts 0.81 g of magnesium with excess butanoic acid. Calculate the maximum volume of hydrogen gas produced at room temperature and pressure. (1 mol of any gas occupies 24 dm³ at r.t.p.; Mg = 24.3 g/mol)
Question 568
2 marks · Easy
Answer and see the solution →Explain why carboxylic acids such as ethanoic acid have a higher pH than hydrochloric acid of the same concentration.
Question 569
1 mark · Easy
Answer and see the solution →State the products formed when dilute butanoic acid reacts with magnesium metal.
Question 570
3 marks · Easy
Answer and see the solution →Ethanoic acid is a weak acid. A student places blue litmus paper into a solution of ethanoic acid and measures the pH.
(a)[1 mark]State the expected colour change of the litmus paper.
(b)[1 mark]Ethanoic acid reacts with sodium carbonate solution. Write the chemical name of the gas produced.
(c)[1 mark]Describe what is meant by a 'weak acid' in terms of ionisation in water.