Alkenes — Paper 2 · IGCSE Sciences - Co-ordinated (Double) 0654

26 Which substance is not a product of an addition reaction of ethene? A B C D H H H H H H H H H C C OH HO C C OH Br C C Br H C C H H H H H H H H H

1 marks

Answer: B

This question in 0654/21 May/June 2017

26 What is the structure of but-2-ene? A CH3–CH2–CH=CH2 B CH3–CH=CH–CH3 C CH3–CH=CH2 D CH3–CH2–CH3

1 marks

Answer: B

This question in 0654/22 Oct/Nov 2017

27 The structures of four hydrocarbons are shown. 1 2 H H H H H H H H C C C C H H C C C H H H H 3 4 H H H H H H H H C C C C C H H C C H H H H H H H H Which of the hydrocarbons change the colour of aqueous bromine? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2017

16 Which dot-and-cross diagram represents the bonding of electrons in a molecule of ethene? A B H H H H C C C C H H H H C D H H H H H C C H H C C H H H H H

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2018

26 Which formula represents but-1-ene? A CH3CH=CH3 B CH3CH2CH2CH3 C CH3CH2CH=CH2 D CH3CH=CHCH3

1 marks

Answer: C

This question in 0654/21 Oct/Nov 2018

26 Ethene reacts with steam to make ethanol in the presence of a catalyst. Which type of reaction occurs? A addition B displacement C oxidation D polymerisation

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2018

26 Three reactions are listed. 1 the addition of hydrogen to ethene 2 the addition of steam to ethene 3 the cracking of long chain alkanes Which reactions produce molecules of a different homologous series from the reactant molecules? A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

1 marks

Answer: D

This question in 0654/21 May/June 2019

27 One molecule of hydrocarbon Q undergoes complete combustion to produce four molecules of carbon dioxide. Hydrocarbon Q has no effect on the colour of bromine water. What is hydrocarbon Q? A butane B butene C propane D propene

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2019

27 Which row describes properties of alkenes? products of structure of molecules complete combustion A contain only carbon and hydrogen CO2 and H2O B contain only carbon and hydrogen CO and H2O C contain only single bonds CO and H2O D contain only single bonds CO2 and H2O

1 marks

Answer: A

This question in 0654/22 May/June 2020

24 The reaction equation for the production of ethanol by an addition reaction is shown. C2H4 + H2O → C2H5OH Which row describes the physical state of water and of ethanol in the reaction vessel? water ethanol A gas gas B gas liquid C liquid gas D liquid liquid

1 marks

Answer: A

This question in 0654/23 May/June 2020

26 What reacts with ethene to form ethanol? A bromine B hydrogen C oxygen D steam

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2020

26 What reacts with ethene to make ethanol? A bromine B hydrogen C steam D yeast

1 marks

Answer: C

This question in 0654/23 Oct/Nov 2020

27 Which reaction produces only one product? A combustion of ethanol B cracking of alkanes C fermentation of sugar solution D reaction of ethene and steam

1 marks

Answer: D

This question in 0654/21 May/June 2021

27 Reactants for three chemical processes are listed. 1 ethene + steam 2 ethene + hydrogen 3 ethene in addition polymerisation Which processes form saturated hydrocarbons? A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

1 marks

Answer: C

This question in 0654/22 May/June 2021

27 Which substances can be produced by cracking? A alkanes only B alkenes only C alkenes and hydrogen only D alkanes, alkenes and hydrogen

1 marks

Answer: D

This question in 0654/23 May/June 2021

27 The cracking of decane molecules is represented by the equation shown. C10H22  Y + 2C3H6 What is Y? A C4H8 B C4H10 C C7H14 D C7H16

1 marks

Answer: B

This question in 0654/21 Oct/Nov 2021

26 Which statements about ethene and but-1-ene are correct? 1 Only ethene reacts with bromine water. 2 They are both formed by cracking alkanes. 3 They both react with steam to form alcohols. 4 They have different general formulae. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

1 marks

Answer: C

This question in 0654/22 Feb/March 2022

26 Which row describes the hydrocarbon CH3CHCH2? homologous series general formula A alkane CnH2n+2 B alkane CnH2n C alkene CnH2n+2 D alkene CnH2n

1 marks

Answer: D

This question in 0654/22 May/June 2022

26 Hydrocarbon X has two carbon atoms in each molecule. It does not decolourise bromine water. Hydrocarbon Y has three carbon atoms in each molecule. It does decolourise bromine water. What is the difference in the number of hydrogen atoms in the molecules of X and Y? A 0 B 1 C 2 D 4

1 marks

Answer: A

This question in 0654/22 Feb/March 2023

27 Which structure represents the addition polymer made from the monomer propene, C3H6? A B CH3 H CH3 H H H H H C C C C C C C C H H H H H H H H C D CH3 CH3 CH3 CH3 CH3 CH3 CH3 CH3 C C C C C C C C H H H H CH3 CH3 CH3 CH3

1 marks

Answer: A

This question in 0654/21 May/June 2023

26 Which formula represents but-1-ene? A CH3CH=CH2 B CH3CH2CH2CH3 C CH3CH2CH=CH2 D CH3CH=CHCH3

1 marks

Answer: C

This question in 0654/23 Oct/Nov 2023

26 The structure of a molecule of compound X is shown. H H C C H H Which two formulas represent compounds that are in the same homologous series as X? A C5H10 and C5H12 B C4H10 and C6H14 C C3H6 and C5H10 D C3H6 and C4H10

1 marks

Answer: C

This question in 0654/21 May/June 2024

26 What is a general formula for unsaturated hydrocarbons? A CnHn+2 B C2nH2n+2 C CnH2n D CnH2n+2

1 marks

Answer: C

This question in 0654/21 Oct/Nov 2024

27 Which substance decolourises aqueous bromine? A B C D H H H H H H H H C C H H C H C C H C C O H H H H H H H H

1 marks

Answer: C

This question in 0654/22 Oct/Nov 2024

27 Reactants for three chemical processes are listed. 1 ethene + steam 2 ethene + hydrogen 3 ethene forming poly(ethene) Which processes form saturated hydrocarbons? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2024

24 Which statements about the addition reactions of ethene are correct? 1 Ethene reacts with hydrogen to form ethane. 2 Ethene reacts with steam to form ethane. 3 Ethene undergoes addition reactions because it is a saturated hydrocarbon. 4 During addition reactions of ethene, only one product is produced. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

1 marks

Answer: B

This question in 0654/21 Oct/Nov 2025

25 A section of polymer X is shown. CH3 H C C H CH3 n Which statement about X is correct? A It is a condensation polymer made from but-1-ene. B It is an addition polymer made from but-1-ene. C It is a condensation polymer made from but-2-ene. D It is an addition polymer made from but-2-ene.

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2025

26 Which type of reaction occurs when ethene reacts with steam? A addition B cracking C displacement D polymerisation

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2025

26 What is the structure of but-2-ene? A CH3–CH=CH2 B CH3–CH2–CH3 C CH3–CH2–CH=CH2 D CH3–CH=CH–CH3

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2025