Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
531–540 of 785
Question 531
3 marks · Normal
Answer and see the solution →A factory can produce ethanol by either fermentation or hydration of ethene. Each method has a different efficiency and energy requirement, as shown in the table below.
Method Percentage Yield (%) Energy Input per Tonne Ethanol (kJ) Fermentation 60 2,500 Hydration of ethene 95 6,000 (a)Calculate the amount of ethanol (in tonnes) produced from 1000 tonnes of raw material by each method.
(i)[1 mark]Fermentation
(ii)[1 mark]Hydration of ethene
(b)[1 mark]Which method requires less energy per tonne of ethanol produced? Show how you use the data to decide.
Question 532
2 marks · Hard
Answer and see the solution →State one reason why ethanol produced by fermentation may need further processing, and one reason why ethanol produced by hydration of ethene is considered more efficient.
Question 533
5 marks · Hard
Answer and see the solution →A chemical company is choosing between fermentation and hydration of ethene to manufacture ethanol.
(a)[2 marks]State one raw material used in each method.
(b)[1 mark]Explain one environmental advantage of using fermentation rather than hydration to produce ethanol.
(c)[1 mark]Describe one disadvantage of fermentation compared to hydration of ethene for industrial production of ethanol.
(d)[1 mark]State one condition or feature of the hydration of ethene process that makes it more efficient industrially than fermentation.
Question 534
2 marks · Hard
Answer and see the solution →Give one reason why the fermentation method for producing ethanol is not as sustainable as it first appears, and one limitation of the hydration of ethene method for future production.
Question 535
5 marks · Easy
Answer and see the solution →This question is about alcohols and what happens when ethanol burns in air.
(a)[1 mark]Name an alcohol with three carbon atoms.
(b)[2 marks]Draw the displayed formula of ethanol, showing all atoms and bonds.
(c)[2 marks]Ethanol reacts with oxygen when it burns. Write the balanced chemical equation for the complete combustion of ethanol.
Question 536
5 marks · Easy
Answer and see the solution →Methanol and ethanol are both alcohols used as fuels.
(a)[1 mark]State the IUPAC name for the alcohol with molecular formula CH4O.
(b)[2 marks]Explain how the –OH functional group in ethanol affects its chemical properties compared to alkanes.
(c)[2 marks]Describe what happens in the combustion of ethanol, including the products formed.
Question 537
5 marks · Easy
Answer and see the solution →Ethanol can be used as a fuel. The equation for its complete combustion is:
(a)[1 mark]State the molecular formula of ethanol.
(b)[1 mark]How many moles of carbon dioxide are made from 1 mole of ethanol in complete combustion?
(c)[3 marks]Calculate the total number of oxygen atoms found in the water produced when 0.5 mol of ethanol burns completely. (Show your working.)
Question 538
5 marks · Easy
Answer and see the solution →Alcohols are used as biofuels. This question is about naming alcohols and their reactions.
(a)[1 mark]Give the IUPAC name for the alcohol with the structural formula CH3CH2CH2OH.
(b)[1 mark]State the homologous series to which ethanol belongs.
(c)[2 marks]Write the word equation for the complete combustion of ethanol.
(d)[1 mark]State one advantage of using ethanol as a fuel.
Question 539
6 marks · Normal
Answer and see the solution →Ethanol is an important organic compound with many uses, including as a fuel and a chemical feedstock.
(a)[1 mark]Describe one observable colour change when ethanol is oxidised by heating with potassium dichromate(VI) in dilute sulfuric acid.
(b)[1 mark]Write a word equation for the oxidation reaction described in part (a).
(c)[2 marks]State the role of sulfuric acid in this oxidation reaction.
(d)[2 marks]Describe how ethanol can be produced by fermentation.
Question 540
6 marks · Normal
Answer and see the solution →A student carries out two experiments: (A) heating ethanol with potassium dichromate(VI) in dilute sulfuric acid, and (B) producing ethanol by fermentation.
(a)[1 mark]In experiment A, state the colour change that occurs when ethanol is successfully oxidised.
(b)[1 mark]Name the final organic product formed in experiment A.
(c)[1 mark]In experiment B, yeast is added to a sugar solution. State one condition required to maximise ethanol production by fermentation.
(d)[3 marks]Complete the table below for each experiment.
Experiment Reactants Product A B