Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Alcohols
130 practice questions
Topics covered
- Drawing and naming the alcohols21 practice questions
- Ethanol burns in air19 practice questions
- Ethanol can be oxidised by heating with potassium dichromate(VI) in dilute sulfuric acid21 practice questions
- Making ethanol by fermentation19 practice questions
- Making ethanol by the hydration of ethene19 practice questions
- Comparing the two methods of producing ethanol20 practice questions
Practice questions
21–30 of 57 · Normal
Question 21
3 marks · Normal
Answer and see the solution →Ethanol is sometimes used to make vinegar by oxidation. Explain, in terms of the laboratory process, how a chemist could use potassium dichromate(VI) and dilute sulfuric acid to produce ethanoic acid from ethanol.
Question 22
4 marks · Normal
Answer and see the solution →The table shows the initial and final colours observed when ethanol is heated with potassium dichromate(VI) and dilute sulfuric acid.
Observation of Colour Changes during Oxidation Test Initial colour Final colour A Orange Green B Orange Orange C Orange Green Explain what has happened in each test. Suggest a reason why the outcome was different in test B.
Question 23
1 mark · Normal
Answer and check →Which statement best explains the role of dilute sulfuric acid in the oxidation of ethanol with potassium dichromate(VI)?
- A.It provides hydrogen ions needed for the reaction.
- B.It acts as a catalyst for ethanol oxidation.
- C.It reacts with ethanol to make ethene.
- D.It neutralises the potassium dichromate(VI).
Question 24
2 marks · Normal
Answer and see the solution →State the reagents and conditions required to oxidise ethanol to ethanoic acid in the laboratory.
Question 25
4 marks · Normal
Answer and see the solution →(a)[1 mark]What is the appearance of the potassium dichromate(VI) solution before ethanol is added?
(b)[2 marks]Describe the appearance of the solution after heating with ethanol.
(c)[1 mark]What does the observed colour change indicate about the reaction?
Question 26
2 marks · Normal
Answer and see the solution →Describe what happens to ethanol when it is heated with potassium dichromate(VI) in dilute sulfuric acid. Include what is formed in the reaction.
Question 27
4 marks · Normal
Answer and see the solution →(a)[1 mark]State the initial colour of potassium dichromate(VI) solution before ethanol is added and heated.
(b)[2 marks]Describe the colour change observed when ethanol is oxidised by heating with potassium dichromate(VI) in dilute sulfuric acid.
(c)[1 mark]Name the ion that causes the final colour observed.
Question 28
3 marks · Normal
Answer and see the solution →A student plans to oxidise ethanol using potassium dichromate(VI) in dilute sulfuric acid. Explain, with reasoning, the role of the sulfuric acid in this reaction and what would happen if it was not included.
Question 29
2 marks · Normal
Answer and see the solution →State two conditions required for the fermentation of glucose to produce ethanol.
Question 30
4 marks · Normal
Answer and see the solution →(a)[2 marks]Describe how ethanol can be made by fermentation of glucose.
(b)[1 mark]State the main product formed if the fermentation is carried out in the presence of air.
(c)[1 mark]Explain why the fermentation reaction is slow if the temperature is below 30°C.