0654.C11.5.03 — Describe the manufacture of alkenes and hydrogen by the cracking of larger alkane molecules using a high temperature and a catalyst: past paper questions
Real questions on 0654.c11.5.03 — describe the manufacture of alkenes and hydrogen by the cracking of larger alkane molecules using a high temperature and a catalyst
The newest 11 of 11 written questions. Open one to see it on the real paper.
- 0973/41 · May/June 2026 · Q8c(i)[1]
(i) Complete the equation for the cracking of C,,H 14° °30° CygHyg CyHg ..........
See it on the paper → - 0973/41 · May/June 2025 · Q8b(i)[2]
Describe how large alkane molecules produced by fractional distillation are changed into smaller alkene molecules.
See it on the paper → - 0973/41 · May/June 2025 · Q8b(ii)[2]
The large alkane C 22 H 46 is changed into butane and an alkene. Complete the balanced symbol equation for this reaction. C 22 H + butane alkene
See it on the paper → - 0973/31 · October/November 2024 · Q11b(ii)[1]
Ethene is made from the breakdown of larger molecules in petroleum. State the name of this process.
See it on the paper → - 0973/41 · October/November 2023 · Q2c(ii)[2]
State the conditions needed for cracking.
See it on the paper → - 0973/42 · May/June 2022 · Q11b[2]
Fractional distillation makes too much gas oil and not enough gasoline. Cracking breaks large hydrocarbon molecules into smaller molecules. State two conditions needed for cracking.
See it on the paper → - 0973/42 · May/June 2022 · Q11c[1]
Cracking involves the breaking of covalent bonds within molecules. Fig. 11.1 shows the structure of dodecane. H H H H H H H H H H H H H C C C C C C C C C C C C H H H H H H H H H H H H H Fig. 11.1 The cracking of dodecane makes a mixture of products. Explain why.
See it on the paper → - 0973/32 · May/June 2021 · Q11e(ii)[1]
Name the process that produces smaller unsaturated hydrocarbon molecules from large saturated hydrocarbon molecules.
See it on the paper → - 0973/41 · May/June 2021 · Q11b(i)[2]
State the conditions needed for cracking.
See it on the paper → - 0973/31 · May/June 2020 · Q11c(iii)[1]
State the name of the chemical reaction that makes alkenes from alkanes.
See it on the paper → - 0973/42 · May/June 2019 · Q2b[1]
Name the process used to convert larger alkane molecules into ethene and hydrogen.
See it on the paper →
What examiners said
The term cracking was not widely known as the correct process. More candidates understood that the process involved high temperatures. The term catalytic cracking was seen quite often.
— Examiner report, May/June 2025, 0973/41 Q8(b)(i) (Cambridge)
The correct formula for butane was only sometimes seen. The most awarded marking point was recognising that the formulas quoted for butane and an alkene balanced with the large alkene given.
— Examiner report, May/June 2025, 0973/41 Q8(b)(ii) (Cambridge)
Candidates found this question challenging with many vague answers such as heat, hot, temperature and pressure. Some candidates also confused a catalyst with a catalytic converter. The best answers about the conditions needed for cracking were a high temperature or a stated high temperature and the need for a catalyst or the need for a high pressure.
— Examiner report, October/November 2023, 0973/41 Q2(c)(ii) (Cambridge)
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