O-LevelChemistryOrganic Chemistry5070/22 · Oct/Nov 2017 · Q49 Marks

Lavandulol is found in lavender plants. CH3 CH2 C=CH−CH2−CH−C CH3 CH3 CH2OH

(a)(i)Give the molecular formula for lavandulol.[1]
(a)(ii)Lavandulol contains an –OH group. Name the homologous series of compounds which contain the –OH group.[1]
(b)Lavandulol is an unsaturated compound. Describe a test for an unsaturated compound. test result[2]
(c)Lavender flowers contain a variety of coloured compounds. These can be extracted from the flowers to give a solution of the coloured compounds. Describe how to use paper chromatography to identify these coloured compounds. You may use a labelled diagram in your answer.[3]
(d)Compound G is found in the leaves of lavender plants. H O H−N−CH2−C−O−H Compound G can undergo polymerisation. Draw a section of the polymer to show two repeat units.[2]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2017). The mark or mark type is shown in brackets.

[1] C10H18O
[1] Alcohol
[1] Bromine / bromine water
[1] Turns colourless
[1] Pigment(s) / dyes / coloured compounds on paper and paper (dipping) in solvent
[1] Spot of dye above solvent level
[1] Measure distance moved by dye and solvent (front)
[1] Calculate Rf value
[1] Compare with known Rf value(s)
[2] Two correct repeat units with amide link e.g. - NH-CH2-C(=O) - NH – CH2 - C(=O) -
[1] If 2 marks not awarded, 1 mark for two amide links drawn correctly

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