CIE Nov 2014 v1 Paper 4 Q8

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T is a saturated alcohol. It was analysed by mass spectroscopy and NMR spectroscopy. In the mass spectrum, the molecular ion peak, M, was at an m/e value of 74 and the ratio of the heights of the M and M+1 peaks was 20.4 : 0.9. 18 PMT (a) (i) Use the ratio of the heights of the M and M+1 peaks to calculate the number of carbon atoms in a molecule of T. (ii) What is the molecular formula of T? (b) The NMR spectrum of T given below shows four absorptions. The absorption at 1.8 ppm is a multiplet and that at 2.5 ppm is a singlet. molecular formula =[3] 11 10 5/ ppm (i) Use this information and your answer to (a)(ii) to deduce the structure of T.UCLES 2014 9701/41/O/N/14<br /> PMT 19 (ii) Describe and explain which type of proton is responsible for each of the absorptions.(iii) The absorption at 1.8 ppm is a multiplet and that at 2.5 is a singlet. State and explain the splitting patterns of the other absorptions, at 0.9 and 3.4 ppm.(iv) Describe and explain how the NMR spectrum of T dissolved in D2O would differ from the one shown.[9] [Total: 12]UCLES 2014 9701/41/O/N/14 [Turn over<br />

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