OCR A Jan 2011 Paper 4 Q6

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6 A company was planning to build a power station that will burn plastic waste. The local residents were concerned about possible emission of pollutants such as dioxanes and aromatic hydrocarbons. The residents employed an independent chemical engineer to advise about possible emissions. 13 Some scientists suspect that dioxanes, such as 1,3-dioxane, and aromatic hydrocarbons may be linked to some types of cancer. 1,3-dioxane (a) Predict the splitting patterns in the proton NMR spectrum of 1,3-dioxane. Identify which protons are responsible for each splitting pattern. In your answer, you should use appropriate technical terms, spelled correctly.[3] TURN OVER FOR QUESTION 6 (b)OCR 2011 Turn over<br />
 (b) The independent chemical engineer investigated an unknown aromatic hydrocarbon. He obtained the mass spectrum and the 13C NMR spectrum of the aromatic hydrocarbon, which are shown below. 14 100 80 60 relative intensity (%) 40 20 10 absorption 20 30 40 50 60 m / z 70 80 90 100 110 200 180 160 140 120 100 80 60 40 20 chemical shift, /ppm The aromatic hydrocarbon is one of four possible isomers. Use the spectra to identify the aromatic hydrocarbon. Show all of your working and explain how you ruled out the other three isomers.OCR 2011<br />
 15aromatic hydrocarbon is:OCR 2011 [6] [Total: 9] END OF QUESTION PAPER<br />

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