Separate samples of liquid phenylethene and solid poly(phenylethene) are shaken with a few drops of orange bromine water.
Which statement correctly describes the observations and the chemical reasoning?
Both mixtures remain orange because the aromatic ring in both compounds prevents any addition reactions from occurring.
Both mixtures turn colourless because both the monomer and the polymer contain reactive carbon-carbon double bonds in their structures.
Only the poly(phenylethene) mixture turns colourless because the polymerisation process creates highly reactive carbon-carbon double bonds.
Only the phenylethene mixture turns colourless because it contains an unsaturated carbon-carbon double bond (C=CC=CC=C), whereas the polymer backbone is saturated with only carbon-carbon single bonds (C−CC-CC−C).
Practise Edexcel GCSE Chemistry Polymers with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.