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
31–40 of 57 · Normal
Question 31
3 marks · Normal
Answer and see the solution →In a fermentation process, 180 g of glucose is completely converted to ethanol and carbon dioxide.
Calculate the mass of ethanol produced.
The equation for fermentation is:
M_r values: glucose (C6H12O6) = 180, ethanol (C2H5OH) = 46
Question 32
3 marks · Normal
Answer and see the solution →Ethanol can be produced by fermentation or by the hydration of ethene.
Explain two advantages and one disadvantage of making ethanol by fermentation instead of from ethene.
Question 33
4 marks · Normal
Answer and see the solution →(a)[2 marks]Data: Rate of ethanol production at different temperatures Temperature (°C) Ethanol produced after 2 days (cm³) 10 3 20 15 30 28 40 10 50 0 Describe the effect of temperature on the amount of ethanol produced after 2 days.
(b)[1 mark]Suggest a temperature range suitable for the fermentation process to produce the most ethanol.
(c)[1 mark]Explain why no ethanol is produced at 50°C.
Question 34
1 mark · Normal
Answer and check →Which statement about fermentation in ethanol production is correct?
- A.Yeast converts glucose to ethanol only at temperatures above 50°C.
- B.Fermentation must be carried out in the presence of air.
- C.Ethanol is produced by yeast enzymes acting on sugars.
- D.Water and carbon dioxide are the only products.
Question 35
2 marks · Normal
Answer and see the solution →State the balanced chemical equation for the fermentation of glucose to produce ethanol.
Question 36
4 marks · Normal
Answer and see the solution →(a)[2 marks]Describe the two main methods used to produce ethanol industrially.
(b)[1 mark]State one condition needed for the hydration of ethene to make ethanol.
(c)[1 mark]Suggest one reason why hydration of ethene is used in some countries instead of fermentation.
Question 37
2 marks · Normal
Answer and see the solution →State the word equation and the balanced symbol equation for the reaction to produce ethanol by the hydration of ethene.
Question 38
4 marks · Normal
Answer and see the solution →(a)[1 mark]State the temperature used in the hydration of ethene.
(b)[1 mark]Give the pressure (in atmospheres) required for this reaction.
(c)[1 mark]Name the catalyst used in the hydration of ethene.
(d)[1 mark]Explain why these conditions (temperature and pressure) are used in industry for this reaction.
Question 39
3 marks · Normal
Answer and see the solution →During the hydration of ethene, only 15% of ethene is converted to ethanol in one pass through the reactor. 1000 mol of ethene are used.
Calculate:
(a)[1 mark]The number of moles of ethene that react.
(b)[1 mark]The number of moles of ethene unreacted after one pass.
(c)[1 mark]Explain, in one sentence, why the unreacted ethene is recycled in the process.
Question 40
4 marks · Normal
Answer and see the solution →The table below shows different industrial runs for the hydration of ethene, with the corresponding conditions and yields.
Run Temperature (°C) Pressure (atm) Catalyst Yield of ethanol (%) A 270 60 phosphoric acid 70 B 300 65 phosphoric acid 81 C 325 70 phosphoric acid 84 D 350 55 phosphoric acid 77 (a)[1 mark]Identify the run with the highest ethanol yield.
(b)[1 mark]State the temperature and pressure for this best-yield run.
(c)[1 mark]Describe how increasing temperature affected yield between runs A, B and C.
(d)[1 mark]Suggest one reason why the yield in run D is lower than in run C, even though the temperature is higher.