Edexcel Jun 2013 Paper 6 Q2

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2 A colourless liquid, compound X, was extracted from raspberries. X has the molecular formula C10H12O2 and contains a benzene ring. (a) What would you expect to see if a sample of compound X was burned in air? (1)(b) A series of tests was carried out on compound X. In each test, state what you can deduce about the structure of compound X from the results described. (i) X forms a white precipitate with aqueous bromine solution. (1)(ii) X forms an orange precipitate with 2,4-dinitrophenylhydrazine. (1)(iii) Fehlings (or Benedicts) solution remains blue when warmed with compound X. (1)*P41653A0516* Turn over<br /> (c) The high resolution proton nmr spectrum of compound X is shown below. This spectrum shows that there are six different proton environments in the molecule of X. The relative number of hydrogen atoms in each environment is indicated on the spectrum. Use this spectrum, the data below and your answers to (a) and (b) to help answer the questions that follow. 3H 2H 2H 1H 2H 2H chemical shift / ppm Nuclear Magnetic Resonance HCC=C alkenes arenes HCC=O aldehyde ketone ester amide acid Ar OH phenol HCO alcohol ether ester OH alcohol Ar H arene ring HC=C alkene TMS Chemical shifts for hydrogen relative to TMS (tetramethylsilane) HCC alkane R 3 CH>R 2CH 2> RCH3 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0/ppm for TMS *P41653A0616*<br /> (i) Which hydrogen atoms in compound X are most likely to have caused the peaks at 6.5 ppm and 7.2 ppm? (1)(ii) Compound X has a side chain containing four carbon atoms attached to the benzene ring. Show all the atoms on this side chain and label each hydrogen environment on the side chain with its splitting pattern. (3)(iii) Suggest the structural formula of X. (1) *P41653A0716* Turn over<br /> (d) Compound X can be extracted from raspberries by steam distillation. Draw a labelled diagram of the apparatus you could use to carry out this steam distillation. (3) (Total for Question 2 = 12 marks) *P41653A0816*<br />

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