CAPE Chemistry Unit 2 · May/June 2019 · Paper 2

31 questions and parts from this paper. Open one to see it in full, then practise it on Quelpr and get it marked against the mark scheme.

1. 1(a)(i)1 markState the name of the starting compound.
2. 1(a)(ii)1 markState the type of reaction which takes place when the compound reacts with sodium hydroxide.
3. 1(a)(iii)3 marksOutline a mechanism for the reaction, using curved arrows to show the movement of electrons. Show clearly the structure of any intermediates formed as well as the final product.
4. 1(b)(i)3 marksState the reagents and condition(s) used to convert benzene into nitrobenzene.
5. 1(b)(ii)5 marksOutline the mechanism for the reaction described in (b) (i).
6. 1(c)(i)3 marksWrite the reagents used for the reactions I, II and III.
7. 1(c)(ii)2 marksState the class of compounds to which E belongs, giving the commercial significance of such compounds.
8. 1(d)(i)3 marksUse the compound ethylamine CH3CH2NH2 and a relevant equation to explain the statement above.
9. 1(d)(ii)4 marksThe pKb values for ethanamide, ethylamine and phenylamine are 14.51, 3.27 and 9.38 respectively. Account for the difference in these pKb values.
10. 1(e)5 marksComplete the table by inserting the appropriate observations and reagents.
11. 2(a)3 marksState the meaning of EACH of the following terms: Electromagnetic radiation, Wavelength, Frequency.
12. 2(b)(i)1 markWrite the formula which relates the speed of light (c), the wavelength of light (λ) and its frequency (v).
13. 2(b)(ii)4 marksUsing the formula from (b) (i), calculate the missing frequencies and wavelengths in Table 2 AND identify the corresponding type of electromagnetic radiation. (c = 3.0 × 10^8 ms⁻¹)
14. 2(c)(i)3 marksComplete Figure 2 by inserting arrows to show ALL possible electron transitions in the molecular orbitals indicated.
15. 2(c)(ii)3 marksList the transitions from (c) (i) which will normally produce absorption in the ultraviolet and visible regions of the electromagnetic spectrum.
16. 2(c)(iii)4 marksThe absorbance of an iron thiocyanate solution containing 0.005 mol Fe/mL was reported as 0.4900 at 540 nm. Using Beer–Lambert's law, A = εcl, calculate the specific absorptivity, including units, of iron thiocyanate,…
17. 2(d)(i)3 marksIdentify the compound and provide justification for Figure 3.
18. 2(d)(ii)2 marksIdentify the compound and provide justification for Figure 4.
19. 2(d)(iii)2 marksIdentify the compound and provide justification for Figure 5.
20. 2(e)(i)4 marksDescribe FOUR steps to be taken by the student in preparing the sample for analysis.
21. 2(e)(ii)1 markGive ONE reason why the plates used for IR spectroscopy are made from NaCl.
22. 3(a)(i)3 marksIdentify EACH of the following components in Figure 6: A, B, C, D, E.
23. 3(a)(ii)3 marksWrite the formulae of the substances in the mixture F in Figure 6.
24. 3(a)(iii)2 marksWrite an equation to represent the reaction at EACH electrode during the production of aluminium.
25. 3(a)(iv)3 marksSuggest THREE factors which may influence the location of a bauxite plant.
26. 3(b)(i)3 marksStarting with sulfur, list the THREE main processes which occur during the production of sulfuric acid.
27. 3(b)(ii)5 marksUsing an appropriate equation, apply the principles of chemical equilibrium to deduce the theoretical conditions for the formation of sulfur trioxide.
28. 3(b)(iii)5 marksDiscuss the actual conditions used in the formation of sulfur trioxide in the contact process. Your response should include conditions of temperature, conditions of pressure, suitability of any catalyst(s) used.
29. 3(b)(iv)1 markState ONE impact of the sulfuric acid industry on the environment.
30. 3(c)(i)3 marksDescribe laboratory tests which would confirm the presence of PO4^3-.
31. 3(c)(ii)2 marksDescribe laboratory tests which would confirm the presence of CN-.