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A-Level ChemistryYear 2023Q4

8   4 This question is about some hydrocarbons. (a) A 2.50 g sample of a hydrocarbon gave 7.59 g of carbon dioxide on complete oxidation. Calculate the empirical formula of the hydrocarbon. (4) Turn over 9   (b) Benzene and ethene react with bromine under different conditions but both reactions involve an electrophile. (i) An electrophile is a substance that (1) A accepts a pair of electrons B accepts an unpaired electron C donates a pair of electrons D donates an unpaired electron (ii) Explain why benzene is resistant to bromination but ethene reacts readily with bromine at room temperature. (4) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (Total for Question 4 = 9 marks)

Paper Source:EDACH339ch0-02-que-20230620.pdf

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Exam Specification Info

This question is part of the UK A-Level Chemistry syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.

Syllabus levelAdvanced Level (A-Level)

SubjectChemistry

Official MarksVariable (2–6 marks)

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