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Infrared spectroscopy and mass spectrometry

Past-paper questions pack

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Questions are numbered; the mark schemes (the answer key) follow on separate pages so the question pages can be handed out alone. www.chemistryaleveltutor.com

OCR AS and A-level Chemistry past-paper questions since 2016 · 61 parts · mark schemes follow the questions · www.chemistryaleveltutor.com · Questions and mark schemes © OCR

1. June 2025 · AS Paper 1 · Q19 · 1 marks ·
19 In a mass spectrum, which alkene is likely to have a fragment ion at m / z = 29? A H2C=CHCH=CH2 B H2C=C(CH3)2 C H3CCH=CHCH3 D H3CCH=CHCH2CH3 Your answer [1]
2. June 2025 · AS Paper 1 · Q20 · 1 marks ·
20 The IR spectrum of a compound is shown below. 100 80 60 transmittance (%) 40 20 0 4000 3000 2000 1500 1000 400 wavenumber / cm–1 Which compound could have produced the IR spectrum? A CH3CH=CH2 B CH3CH2CHO C CH3CH2CH2OH D CH3CH2COOH Your answer [1]
3. June 2025 · AS Paper 2 · Q6(a)(i) · 2 marks ·
6 Compound A is a ketone. It has the following structure. O H3C C CH2 CH3 (a) The mass spectrum of compound A is shown below. 100 P 80 Relative intensity 60 40 Q 20 0 10 15 20 25 30 35 40 45 50 55 60 65 70 75 m / z (i) Draw structures for the ions responsible for peak P and peak Q. ion responsible for peak P ion responsible for peak Q [2]
4. June 2025 · AS Paper 2 · Q6(a)(ii) · 1 marks ·
(ii) Explain why there is a small peak at m / z = 73 .......................................................................................................................................................... ..................................................................................................................................................... [1]
5. June 2025 · AS Paper 2 · Q6(b)(i) · 1 marks ·
(b) Compound B is a non-cyclic structural isomer of Compound A. The infrared spectrum of Compound B is shown below. 100 Transmittance (%) 50 0 4000 3000 2000 1500 1000 500 Wavenumber (cm–1) (i) State the effect infrared radiation has on covalent bonds. .......................................................................................................................................................... ..................................................................................................................................................... [1]
6. June 2025 · AS Paper 2 · Q6(b)(ii) · 2 marks ·
(ii) Identify two functional groups which are likely to be present in Compound B but are not present in Compound A. Explain your answers. Functional group .............................................................................................................................. .......................................................................................................................................................... .......................................................................................................................................................... Explanation ...................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... [2]
7. June 2025 · Paper 2 · Q11 · 1 marks ·
11 Which molecule does not produce a mass spectrum containing a peak at m/z = 29? OH A O B O C O O D O OH Your answer [1]
8. June 2025 · Paper 2 · Q12 · 1 marks ·
12 Which process does not involve infrared radiation? A Catalytic ozone depletion B Monitoring toxic gases in the air C Measuring ethanol in breathalyser tests D Global warming Your answer [1]
9. June 2025 · Paper 2 · Q23(a) · 4 marks ·
23 This question is about spectral analysis. (a) Compound K, C4H10O, is refluxed with H2SO4 to form a mixture of compound L and compound M. The infrared spectrum of compound K is shown. 100 50 Transmittance (%) 0 4000 3000 2000 1500 1000 500 Wavenumber / cm−1 Compound L and compound M are analysed using 13C NMR spectroscopy. • The 13C NMR spectrum of compound L has 4 peaks. • The 13C NMR spectrum of compound M has 2 peaks. Suggest the functional group in compound K, showing your reasoning, and suggest possible structures for compound K, compound L and compound M. Functional group .............................................................. Reasoning ........................................................................................................................................ Possible structure K L M [4]
10. June 2025 · Paper 2 · Q23(b) · 6 marks ·
(b)* An unknown organic compound N is analysed and produces the following results. Elemental analysis by mass C, 62.07%; H, 10.34%; O, 27.59% Mass spectrum 100 80 60 Relative intensity 40 20 0 10 20 30 40 50 60 70 80 90 100 110 120 m / z Proton NMR spectrum Expansion of multiplet 3 6 2 1 6 5 4 3 2 1 0 Chemical shift, δ / ppm The numbers by the peaks are the relative peak areas. Determine the structure of the compound N, showing all your reasoning. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..................................................................................................................................................... [6] Extra answer space if required. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..........................................................................................................................................................
11. June 2024 · AS Paper 1 · Q19 · 1 marks ·
19 Which statement about infrared radiation (IR) is not correct? A Absorption of IR by molecules such as CO2, H2O and CH4 has been linked to global warming. B IR causes CFC molecules to produce chlorine radicals that initiate ozone breakdown in the upper atmosphere. C IR causes some covalent bonds to vibrate more and absorb energy. D IR is used in modern breathalysers to detect ethanol. Your answer [1]
12. June 2024 · AS Paper 1 · Q20 · 1 marks ·
20 An alcohol CH3CH2CH(CH3)OH produces a mass spectrum. The mass spectrum contains a large fragment ion at m/z = 45. What is the possible identity of this fragment ion? A CH2CHOH+ B CH2CH2OH+ C CH3CHOH+ D CH3CH2CH+ Your answer [1]
13. June 2024 · AS Paper 2 · Q6 · 6 marks ·
6* Compound X is an organic compound with two functional groups. Compound X has the percentage composition by mass: C, 40.91%; H, 4.54%; O, 54.55%. Compound X does not decolourise bromine water. A scientist analyses compound X using mass spectrometry and infrared spectroscopy. Mass spectrum of X 100 80 60 relative intensity 40 20 0 10 20 30 40 50 60 70 80 90 100 110 m / z IR spectrum of X 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Use all the information to determine a possible structure of compound X. In your answer, make it clear how your conclusions are linked to the evidence. [6] .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... Extra answer space if required .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..........................................................................................................................................................
14. June 2024 · Paper 2 · Q7 · 1 marks ·
7 Which statement gives a valid scientific reason for global warming? A Infrared radiation causes bonds in CH4 molecules to vibrate more. B Infrared radiation causes O2 molecules to vibrate more. C Ultraviolet radiation causes bonds in CO2 to vibrate more. D Ultraviolet radiation causes bonds in CFC molecules to break. Your answer [1]
15. June 2024 · Paper 2 · Q11 · 1 marks ·
11 Which compound could have produced the IR spectrum shown below? 100 Transmittance (%) 50 0 4000 3000 2000 1500 1000 500 Wavenumber / cm–1 A HOCH2CHO B CH3CH2COOH C CH3CH2COOCH3 D (CH3)2C(OH)COOH Your answer [1]
16. June 2024 · Paper 2 · Q24 · 6 marks ·
24* Analysis of an unknown organic compound J produces the following results. Elemental analysis by mass of compound J C, 80.60%; H, 7.46%; O, 11.94% Mass spectrum of compound J 100 80 60 Relative intensity 40 20 0 25 50 75 100 125 m / z IR spectrum of compound J 100 Transmittance (%) 50 0 4000 3000 2000 1500 1000 500 Wavenumber / cm−1 Proton NMR spectrum of compound J 5 3 1 1 10 8 6 4 2 0 Chemical shift, δ / ppm The numbers by the peaks are the relative peak areas. Determine the structure of compound J, showing all your reasoning. [6] .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... Extra answer space if required. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..........................................................................................................................................................
17. June 2023 · AS Paper 1 · Q19 · 1 marks · AO2
19 An organic compound produces the infrared spectrum below. 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Which compound could have produced this IR spectrum? A CH3CH2CH=CH2 B CH3CHOHCH2CH3 C CH3CH2COCH3 D (CH3)2CHCOOH Your answer [1]
18. June 2023 · AS Paper 1 · Q20 · 1 marks · AO2
20 Pentan-2-ol and pentan-3-ol are structural isomers with the molecular formula C5H12O and Mr = 88. The isomers can be distinguished from the fragment ions in their mass spectra. Which fragment ion would you expect to be present in only one of these isomers? A m/z = 29 B m/z = 45 C m/z = 59 D m/z = 73 Your answer [1]
19. June 2023 · Paper 2 · Q10 · 1 marks · AO2
10 Which ester is most likely to produce a mass spectrum with a fragment ion at m / z = 43? OH O A H3C C C O CH3 CH3 O B HO CH2 C O CH2CH2CH3 OH O C H3C CH CH2 C O CH3 OH O D CH3CH2 C C O CH2CH2OH CH3 Your answer [1]
20. June 2023 · Paper 2 · Q11 · 1 marks · AO2
11 The infrared spectrum of an organic compound is shown below. 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Which compound could have produced this spectrum? A COOH B H3C OCOCH3 C HO CHO D HOCH2 OCH3 Your answer [1]
21. June 2023 · Paper 2 · Q23 · 6 marks · AO1, 3
23* An unknown organic compound is analysed. The results are shown below. Addition of 2,4-DNP No visible change Elemental analysis by mass C, 66.63%; H, 11.18%; O, 22.19% Mass spectrum Molecular ion peak at m / z = 144.0 IR spectrum 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Proton NMR spectrum The numbers by each peak are the relative peak areas. 9 2 3 2 5 4 3 2 1 0 chemical shift, δ / ppm Use the information to identify the organic compound. Show all your reasoning. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..................................................................................................................................................... [6] Additional answer space if required. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..........................................................................................................................................................
22. June 2022 · AS Paper 1 · Q19 · 1 marks · AO2
19 Which organic compound could have produced the infrared spectrum below? 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 A CH3COCH2CH3 B CH3CH2CHOHCH3 C CH3COCH2CH2OH D CH3CH2COOH Your answer [1]
23. June 2022 · AS Paper 1 · Q20 · 1 marks · AO2
20 Which alcohol is likely to have fragment ions at m / z = 15, 29 and 43 in its mass spectrum? OH A B OH OH C OH D Your answer [1]
24. June 2022 · Paper 2 · Q2 · 1 marks · AO1
2 Which statement about absorption of radiation is correct? A Infrared radiation can result in the breakdown of the ozone layer. B Ultraviolet radiation can cause some polymers to photodegrade to benefit the environment. C Ultraviolet radiation is linked to global warming. D Ultraviolet radiation is used in modern breathalysers to measure ethanol in the breath. Your answer [1]
25. June 2022 · AS Paper 2 · Q6 · 6 marks · AO3
6* The organic compound A is unsaturated and is a trans stereoisomer. Compound A has the following composition by mass: C, 55.8%; H, 7.0%; O, 37.2%. The mass spectrum and the infrared spectrum of compound A are shown below. Mass spectrum 100 80 60 relative intensity 40 20 0 10 20 30 40 50 60 70 80 90 100 110 120 m / z Infrared spectrum 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Use the information to determine the structure of compound A. Explain your reasoning and show your working. [6] .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... Additional answer space if required. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..........................................................................................................................................................
26. June 2022 · Paper 2 · Q11 · 1 marks · AO2
11 The infrared spectrum of an organic compound is shown below. 100 Transmittance (%) 0 4000 3000 2000 1500 1000 500 Wavenumber / cm–1 Which compound could have produced this spectrum? A H2C=CHCH2CH2OH B CH3COOCH2CH3 C H2NCH2COOCH3 D (CH3)2CHCONH2 Your answer [1]
27. June 2022 · Paper 2 · Q16(b)(v) · 4 marks · AO2
(v) Compounds D and E are two more structural isomers of C6H12. Compounds D and E do not show stereoisomerism. Table 16.1 shows NMR and infrared (IR) spectral data for D and E. Number of peaks in Number of peaks in IR peak at 1H NMR spectrum 13C NMR spectrum 1620–1680 cm–1 D 1 1 No E 1 2 Yes Table 16.1 Draw the structures of D and E and explain how the spectral data in Table 16.1 provides evidence for the structures. D E ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ...................................................................................................................................... [4]
28. June 2022 · Paper 2 · Q18(b) · 4 marks · AO1, 2, 3
(b) A student is provided with two unknown carbonyl compounds, F and G. The compounds are analysed and found to have identical percentage compositions by mass: C: 62.07%; H: 10.34%; O: 27.59% The mass spectra of the two compounds are shown below. Mass spectrum of F 100 80 60 Relative intensity 40 20 0 10 15 20 25 30 35 40 45 50 55 60 65 70 75 m / z Mass spectrum of G 100 80 60 Relative intensity 40 20 0 10 15 20 25 30 35 40 45 50 55 60 m / z Use the results to identify the structures of the two compounds. Include relevant peaks present in the mass spectrum of each compound. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... F G [4]
29. November 2021 · AS Paper 1 · Q19 · 1 marks · AO1
19 Which statement about absorption of radiation is correct? A Absorption of IR radiation can break covalent bonds, forming radicals. B Absorption of IR radiation causes covalent bonds to vibrate more. C Absorption of UV radiation is a major cause of global warming and climate change. D Absorption of UV radiation is used in modern breathalysers to measure ethanol in the breath. Your answer [1]
30. November 2021 · AS Paper 1 · Q26 · 5 marks · AO3
26 An organic compound E contains C, H and O only. The mass and infrared spectra of organic compound E are shown below. Mass spectrum 100 80 60 relative intensity 40 20 0 10 20 30 40 50 60 70 80 90 m / z Infrared spectrum 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Analyse this information to suggest two different possible structures for compound E. Explain your reasoning. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... Structures [5]
31. November 2021 · Paper 2 · Q11 · 1 marks ·
11 Which compound could have produced the IR spectrum below? 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 A (CH3)2CHCHO B (CH3)2CHCOOH C CH3CH(OH)CH=CH2 D CH3COCH(OH)CH3 Your answer [1]
32. November 2021 · Paper 2 · Q12 · 1 marks ·
12 Which peak would be in the mass spectrum of propanal, CH3CH2CHO, but not in the mass spectrum of propanone, CH3COCH3? A m /z = 15 B m /z = 29 C m /z = 43 D m /z = 58 Your answer [1]
33. November 2021 · Paper 2 · Q20(b)(ii) · 6 marks · AO1, 3
(ii) The pure sample of C is analysed to give the following results. Percentage composition by mass: C, 31.44%; H, 1.31%; N, 18.34%; O, 48.91%. The mass spectrum of C shows a molecular ion peak at m /z = 229.0 The 13C NMR spectrum of C is shown below. 160 140 120 100 80 60 40 20 0 chemical shift, δ / ppm The table shows directing effects for different groups in the electrophilic substitution of aromatic compounds. Directing effect 2- and 4- directing 3-directing –OH –NO2 Group –NH2 Analyse all the information to suggest the structure for C. Show all your reasoning. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... compound C [6]
34. November 2021 · Paper 3 · Q5(c) · 6 marks · AO3
(c)* This question is about two reactions of ammonia. Reaction 1 Excess ammonia is reacted with 4.77 g of copper(II) oxide. The reaction produces 3.81 g of solid E, liquid F and 0.560 g of gas G, which has a volume of 480 cm3 at RTP. Reaction 2 Ammonia reacts with compound H to form compound I, C2H5NO, and chloride salt J. The IR spectrum of I is shown below. 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Identify E, F, G, H, I and J, and write equations for the two reactions. Show your reasoning. 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35. November 2020 · AS Paper 1 · Q20 · 1 marks · AO2
20 The mass spectrum of a carboxylic acid contains peaks at m /z = 29 and m /z = 102. Which compound could have produced the spectrum? O A OH OH B O OH C O OH D O Your answer [1]
36. November 2020 · AS Paper 2 · Q5(f) · 6 marks · AO2, 3
(f)* The structures of A–F are repeated below. OH OH OH A B C OH OH OH D E F Compound X is one of the alcohols A–F. A student refluxes compound X with acidified potassium dichromate(VI) as an oxidising agent. A pure sample of the organic product Y is obtained from the resulting mixture. The mass spectrum and IR spectrum of Y are shown below. Mass spectrum of Y 100 80 relative 60 intensity 40 20 0 10 20 30 40 50 60 70 80 90 m / z IR spectrum of Y 100 transmittance 50 (100%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Using this information, identify compound X and product Y, and write an equation for the formation of product Y from compound X. You may use [O] to represent the oxidising agent. In your answer you should make clear how your conclusions are linked to the evidence. [6] ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... Additional answer space if required ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ...................................................................................................................................................
37. November 2020 · Paper 2 · Q20(b) · 2 marks · AO3
(b) The organic layer in the distillate was analysed by IR spectroscopy. The IR spectrum is shown below. 100 Transmittance (%) 50 0 4000 3000 2000 1500 1000 500 Wavenumber / cm–1 Explain how the IR spectrum of the organic layer suggests that cyclopentene has been formed and that the reaction is incomplete. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [2]
38. November 2020 · Paper 2 · Q22(b) · 6 marks · AO3
(b)* Determine the structure of compound I, showing all your reasoning. [6] ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... Additional answer space if required ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ...................................................................................................................................................
39. June 2019 · AS Paper 1 · Q18 · 1 marks · AO2
18 Which compound is not likely to have a fragment ion at m / z = 43 in its mass spectrum? H H O A H C C C H H OH H O B H C C H OH H CH3 H C H C C C OH H H H H H H D H C C C OH H H H Your answer [1]
40. June 2019 · AS Paper 1 · Q19 · 1 marks · AO1
19 Which statement about infrared radiation is not correct? A The energy from IR radiation causes some covalent bonds to vibrate more. B Absorption of IR radiation by some atmospheric gases is linked by some scientists to global warming. C IR radiation is used to monitor gases causing air pollution. D The action of IR radiation on CFCs in the upper atmosphere leads to the formation of chlorine radicals. Your answer [1]
41. June 2019 · AS Paper 1 · Q20 · 1 marks · AO2
20 An unknown compound produces the infrared spectrum below. 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Which compound could have produced the infrared spectrum? O A OH O B HO OH C O D Your answer [1]
42. June 2019 · AS Paper 2 · Q3(b)(i) · 1 marks · AO1
(b) The mass spectrum of 1-iodopentane is shown below. 100 Z 80 relative 60 Y intensity 40 20 X 0 20 40 60 80 100 120 140 160 180 200 m/z (i) What information is given by the peak labelled X (m/z = 198)? ...................................................................................................................................... [1]
43. June 2019 · AS Paper 2 · Q3(b)(ii) · 2 marks · AO3
(ii) Write the structural formulae of the ions responsible for the peaks labelled Y and Z. Y (m/z = 71) ....................................................................................................................... Z (m/z = 43) .................................................................................................................. [2]
44. June 2019 · AS Paper 2 · Q3(c)(ii) · 2 marks · AO3
(ii) Suggest one similarity and one difference between the mass spectra of 1-iodopentane and 2-iodo-2-methylbutane. Similarity ............................................................................................................................ ........................................................................................................................................... Difference .......................................................................................................................... ...................................................................................................................................... [2]
45. June 2019 · Paper 2 · Q18(e)(ii) · 2 marks · AO2
(ii) The mass spectrum of ester C is shown below. 100 Y 80 60 Relative intensity 40 Z 20 0 10 20 30 40 50 60 70 80 90 100 m / z Suggest possible structures for the species responsible for peaks Y and Z in the mass spectrum. Y Z [2]
46. June 2019 · Paper 2 · Q21 · 6 marks ·
21* Analysis of an unknown organic compound produced the following results. Elemental analysis by mass C: 73.17%; H: 7.32%; O: 19.51% Mass spectrum Molecular ion peak at m / z = 164.0 Infrared spectrum 100 Transmittance (%) 50 0 4000 3000 2000 1500 1000 500 Wavenumber / cm–1 1H NMR spectrum in D2O 3 4 3 1 8 7 6 5 4 3 2 1 0 Chemical shift, d / ppm The numbers by the peaks are the relative peak areas. Use the results to suggest one possible structure for the unknown compound. Show all your reasoning. [6] .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... Additional answer space if required .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..........................................................................................................................................................
47. June 2018 · AS Paper 1 · Q20 · 1 marks ·
20 Which alcohol is likely to have a fragment ion at m / z = 31 in its mass spectrum? A CH3CH2CH(OH)CH3 B CH3CH2CH2C(OH)(CH3)2 C CH3CH(OH)CH2CH2CH3 D (CH3)2CHCH2OH Your answer [1]
48. June 2018 · AS Paper 1 · Q25(b)(ii) · 2 marks ·
(ii) The infrared (IR) spectrum for C2H5CHBrCH3 is shown in Fig. 25.2. The C–Br bond absorption is labelled. 100 transmittance 50 (%) C–Br 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Fig. 25.2 Outline how IR spectroscopy could be used to show that the bromoalkane functional group has reacted and that the alcohol functional group has formed. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ...................................................................................................................................... [2]
49. June 2018 · AS Paper 2 · Q7 · 6 marks ·
7* Compound F is a trans stereoisomer which is a useful intermediate in organic synthesis. The results of elemental and spectral analysis of compound F are shown below. Percentage composition by mass: C, 68.6 %; H, 8.6 %; O, 22.8 %. Infrared spectrum 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Mass spectrum 100 80 60 relative intensity 40 20 0 10 20 30 40 50 60 70 80 m/z In the mass spectrum, the peak with the greatest relative intensity is caused by the loss of a functional group from the molecular ion of compound F. Determine the structure of compound F. Explain your reasoning and show your working. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..................................................................................................................................................... [6]
50. June 2018 · Paper 2 · Q9 · 1 marks ·
9 Which compound could have produced the IR spectrum below? 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 A CH3CH2OH B CH3CHOHCN C CH3COOH D CH3CONH2 Your answer [1]
51. June 2018 · Paper 2 · Q12 · 1 marks ·
12 The mass spectrum of (CH3)2CHCH2OH is shown below. 100 80 60 relative intensity 40 20 0 10 20 30 40 50 60 70 80 90 m /z Which ion is responsible for the peak with the greatest relative intensity? A CHCH2OH+ B CH3CH2CH+ C (CH3)2CH+ D CH3CO+ Your answer [1]
52. June 2018 · Paper 2 · Q21(c)(ii) · 3 marks ·
(ii) A general structure for esters J, L and M is shown below. O C R O HO Where ‘R’ is an alkyl group. Use the mass spectrometry results to deduce possible structures for esters J, L and M. J L M [3]
53. June 2018 · Paper 2 · Q22(d) · 6 marks ·
(d)* A scientist is researching compounds that might be suitable as fuel additives. One of the compounds gives the analytical results below. Elemental analysis by mass: C: 54.54%; H: 9.10%; O: 36.36% Mass spectrum: Molecular ion peak at m/z = 132.0 1H NMR spectrum in D2O 6 3 1 5 4 3 2 1 0 chemical shift,  / ppm The numbers by the peaks are the relative peak areas. When the spectrum is run without D2O, there are two additional peaks with the same relative peak areas at 11.0 ppm and 3.6 ppm. Use the information provided to suggest a structure for the compound. Show all your reasoning. [6] ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... Additional answer space if required. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ...................................................................................................................................................
54. June 2017 · AS Paper 1 · Q19 · 1 marks ·
19 An alcohol A is heated under reflux with sulfuric acid and potassium dichromate(VI). The organic compound formed produces the infrared spectrum below. 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Which compound could be alcohol A? A OH OH B C OH D HO Your answer [1]
55. June 2017 · AS Paper 1 · Q20 · 1 marks ·
20 Which alcohol is not likely to have a fragment ion at m / z = 43 in its mass spectrum? A CH3CH2CH(OH)CH3 B CH3CH2CH2CH2OH C CH3CH(OH)CH2CH2CH3 D (CH3)2CHCH2OH Your answer [1]
56. June 2017 · AS Paper 2 · Q4(b)(ii) · 2 marks ·
(ii) The mass spectrum of alcohol C is shown below. Item removed due to third party copyright restrictions. Write structural formulae for the ions responsible for peak X and peak Y. X = Y = [2]
57. June 2017 · AS Paper 2 · Q5(c) · 4 marks ·
(c) Compound D is a neutral compound which is a structural isomer of propanoic acid, CH3CH2COOH. The infrared spectrum of compound D is shown below. Item removed due to third party copyright restrictions. Suggest two possible structures of compound D. Explain all your reasoning. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [4]
58. June 2017 · Paper 2 · Q20(a) · 3 marks · AO1
20 A chemist analyses a naturally occurring aromatic compound. (a) The percentage composition and mass spectrum of the compound are shown below. Percentage composition by mass: C, 70.58%; H, 5.92%; O, 23.50%. Mass spectrum 100 80 60 relative intensity 40 20 0 25 50 75 100 125 150 m /z Determine the molecular formula of the compound. Show your working. molecular formula = ......................................................... [3]
59. June 2017 · Paper 2 · Q21 · 6 marks ·
21* Compound L is an organic compound containing carbon, hydrogen and oxygen only. The 1H NMR spectrum of compound L is shown below. The numbers by the peaks are the relative peak areas. 9 3 2 2 5 4 3 2 1 0 chemical shift, / ppm δ Compound L is refluxed with aqueous hydrochloric acid, forming two organic compounds M and N. The infrared spectra of M and N are shown below. Infrared spectrum of M Item removed due to third party copyright restrictions. Infrared spectrum of N 100 transmittance (%) 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 Use the information provided to suggest a structure for compound L. Show all of your reasoning. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... .................................................................................................................................................... [6]
60. June 2017 · Paper 3 · Q1(b) · 1 marks ·
(b) Why are scientists concerned about the release of methane into the atmosphere? ................................................................................................................................................... ................................................................................................................................................... ............................................................................................................................................. [1]
61. June 2016 · AS Paper 2 · Q7 · 6 marks · AO3
16 7* Organic compound C has the following percentage composition by mass: C, 54.5%; H, 9.1%; O, 36.4%. The infrared spectrum and mass spectrum of compound C are shown below. 100 transmittance 50 (%) 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 100 80 60 relative intensity 40 20 0 10 20 30 40 50 60 70 80 90 m / z In the mass spectrum, a secondary carbocation is responsible for the peak with the greatest relative intensity. 17 Identify compound C. In your answer you should make clear how your conclusion is linked to all the evidence. .......................................................................................................................................................... .......................................................................................................................................................... .......................................................................................................................................................... ..................................................................................................................................................... [6]

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11. June 2024 · AS Paper 1 · Q19
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22. June 2022 · AS Paper 1 · Q19
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24. June 2022 · Paper 2 · Q2
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25. June 2022 · AS Paper 2 · Q6
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26. June 2022 · Paper 2 · Q11
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27. June 2022 · Paper 2 · Q16(b)(v)
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28. June 2022 · Paper 2 · Q18(b)
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29. November 2021 · AS Paper 1 · Q19
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30. November 2021 · AS Paper 1 · Q26
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31. November 2021 · Paper 2 · Q11
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32. November 2021 · Paper 2 · Q12
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33. November 2021 · Paper 2 · Q20(b)(ii)
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34. November 2021 · Paper 3 · Q5(c)
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35. November 2020 · AS Paper 1 · Q20
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36. November 2020 · AS Paper 2 · Q5(f)
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37. November 2020 · Paper 2 · Q20(b)
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38. November 2020 · Paper 2 · Q22(b)
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39. June 2019 · AS Paper 1 · Q18
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40. June 2019 · AS Paper 1 · Q19
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41. June 2019 · AS Paper 1 · Q20
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42. June 2019 · AS Paper 2 · Q3(b)(i)
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43. June 2019 · AS Paper 2 · Q3(b)(ii)
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45. June 2019 · Paper 2 · Q18(e)(ii)
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47. June 2018 · AS Paper 1 · Q20
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49. June 2018 · AS Paper 2 · Q7
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50. June 2018 · Paper 2 · Q9
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51. June 2018 · Paper 2 · Q12
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52. June 2018 · Paper 2 · Q21(c)(ii)
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53. June 2018 · Paper 2 · Q22(d)
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54. June 2017 · AS Paper 1 · Q19
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56. June 2017 · AS Paper 2 · Q4(b)(ii)
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58. June 2017 · Paper 2 · Q20(a)
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60. June 2017 · Paper 3 · Q1(b)
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61. June 2016 · AS Paper 2 · Q7
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