plumiBond fission and radicals: OCR A‑Level Chemistry A questions
OCR A-Level Chemistry A past-paper questions on 4.1.1.4 Bond fission and radicals, 2016–2025, with mark schemes and examiner’s reports where available.
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Q4(d)(ii)
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Open the full PDFQ19(c)(ii)
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All 8 questions on Bond fission and radicals, as a list
- June 2025, AS Paper 2, Q4(d)(ii) (1 mark): The first step in the mechanism of the reaction is the homolytic fission of a Br–Br bond. Explain what is meant by homolytic fission. [1]
- November 2021, AS Paper 2, Q2(a) (1 mark): What is meant by a radical? [1]
- November 2021, AS Paper 2, Q2(b) (1 mark): Name the type of bond breaking that occurs in a radical substitution reaction. [1]
- November 2020, Paper 2, Q19(c)(ii) (2 marks): Explain why the mechanism in (c)(i) involves heterolytic fission. [2]
- June 2019, Paper 2, Q20(a)(ii) (2 marks): Draw structures to show the products in the reaction mechanism below. H H + O [2]
- June 2019, Paper 2, Q20(a)(iii) (2 marks): Use the mechanism in (ii) to explain what is meant by heterolytic fission. [2]
- June 2017, AS Paper 2, Q5(d)(iii) (1 mark): The first step in the reaction mechanism involves homolytic fission of a chlorine molecule to form two chlorine radicals. Why is this step an example of homolyt
- June 2017, AS Paper 2, Q5(d)(v) (1 mark): Draw the displayed formula of the radical formed in the first propagation step. Use a dot,•, to show the position of the unpaired electron. [1]
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