A-LevelChemistryHalogen derivatives9701/12 · May/June 2023 · Q291 Mark

When bromoethane reacts with hot ethanolic sodium hydroxide a colourless gas is formed. This gas decolourises aqueous bromine. What is the colourless gas?

A1,2-dibromoethane

Bethanol

Cethene

Dhydrogen bromide

✓ Correct answer

C: ethene

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Topic: Halogen derivatives, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source: A-Level Chemistry, May/June 2023 Paper 1 Variant 2, question 29.

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