CSEC Chemistry · January 2007 · Paper 2

48 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)4 marksUsing the graph paper provided on page 3, plot the data for the solubility of R and T given in Table 1.
2. 1(a)(ii)1 markDescribe the effect of increasing temperature on the solubilities of R and T.
3. 1(a)(iii)1 markDetermine the temperature at which the solubilities of R and T are equal.
4. 1(a)(iv)1 markDetermine the solubility of T at 75°C.
5. 1(a)(v)1 markWhich of the two salts is more soluble at 5°C?
6. 1(a)(vi)3 marksSuggest a way for obtaining an essentially pure sample of R from a sample which has been contaminated with a small amount of T.
7. 1(b)(i)1 markComplete Table 2 below by writing the inferences for tests carried out on Solid W. Test: A sample of Solid W is moistened with sodium hydroxide solution and the mixture heated. Moist red and moist blue litmus are held…
8. 1(b)(ii)2 marksComplete Table 2 below by writing the inferences for tests carried out on Solid W. Test: To an aqueous solution of W, a few drops of acidified silver nitrate are added, followed by aqueous ammonia. Observation: White…
9. 1(b)(iii)3 marksComplete Table 2 below by writing the inferences for tests carried out on Solid W. Test: To an aqueous solution of W, a solution containing barium ions is added. Observation: A white precipitate is formed.
10. 1(b)(iv)2 marksComplete Table 2 below by writing the inferences for tests carried out on Solid W. Test: Dilute hydrochloric acid is added to the mixture from (iii) above. Observation: The precipitate is insoluble in the acid. (Ionic…
11. 1(c)(i)2 marksProcedure:
12. 1(c)(ii)3 marksDraw a fully labelled diagram of the apparatus required to conduct your experiment.
13. 1(c)(iii)2 marksData to be collected:
14. 1(c)(iv)2 marksSAMPLE calculation to be performed to determine the heat of combustion per mole of the fuel:
15. 1(c)(v)2 marksTWO possible sources of error in your experiment:
16. 2(a)(i)3 marksIn order to adapt the electrolytic cell in Figure 1 for the purification of copper, what material may be used as the cathode?
17. 2(a)(ii)1 markIn order to adapt the electrolytic cell in Figure 1 for the purification of copper, what material may be used as the anode?
18. 2(a)(iii)1 markIn order to adapt the electrolytic cell in Figure 1 for the purification of copper, what material may be used as the electrolyte?
19. 2(b)(i)3 marksAs electrolysis proceeds, describe the changes expected to be observed at the cathode.
20. 2(b)(ii)1 markAs electrolysis proceeds, describe the changes expected to be observed at the anode.
21. 2(b)(iii)1 markAs electrolysis proceeds, describe the changes expected to be observed in the electrolyte.
22. 2(c)(i)2 marksWrite half-equations for the reactions occurring at the cathode.
23. 2(c)(ii)1 markWrite half-equations for the reactions occurring at the anode.
24. 2(d)(i)2 marksCalculate the quantity of electricity passed in coulombs.
25. 2(d)(ii)3 marksCalculate the mass of copper deposited. [Relative Atomic Mass of Cu = 64, Faraday's constant = 96500 coulombs]
26. 2(e)2 marksIn addition to extraction of metal from their compounds, electrolytic processes are also widely used to protect metals from corrosion, as well as to make them attractive. Name TWO such electrolytic processes.
27. 3(a)(i)1 markOver what range of temperatures and pressures is ammonia NORMALLY produced by the Haber process?
28. 3(a)(ii)a)2 marksBased on the information given in Figure 2, deduce whether increased yields of ammonia would result from conditions of high or low temperature.
29. 3(a)(ii)b)1 markBased on the information given in Figure 2, deduce whether increased yields of ammonia would result from conditions of high or low pressure.
30. 3(a)(iii)2 marksSuggest TWO reasons why ammonia is not usually produced at 100°C and 1200 atm.
31. 3(a)(iv)2 marksWith reference to the properties of ammonia, nitrogen and hydrogen, suggest ONE way that ammonia can be separated from the other gases. Give a reason for your answer.
32. 3(b)(i)2 marksWrite a balanced equation for the reaction between chlorine and ammonia.
33. 3(b)(ii)2 marksBoth NH4Cl and NH2Cl dissolve in water. Aqueous NH4Cl conducts electricity, but aqueous NH2Cl does not. What does this information suggest about the type of bonding in NH4Cl and in NH2Cl?
34. 3(b)(iii)2 marksDraw a dot-cross diagram to show the bonding in NH2Cl.
35. 3(b)(iv)2 marksSuggest ONE reason why NH2Cl dissolves in water.
36. 4(a)(i)7 marksComplete Table 3 below by drawing the displayed structure, and writing the name of EACH of the compounds, X, E and D.
37. 4(a)(ii)1 markName the reagent, q, required to convert X to D in Figure 3.
38. 4(b)(i)2 marksIdentify the homologous series to which Compounds X and E belong. Compound X: Compound E:
39. 4(b)(ii)a)2 marksState ONE physical property of Compound X.
40. 4(b)(ii)b)1 markState ONE physical property of Compound E.
41. 4(c)3 marksBased on your knowledge of the solubilities of Compounds X and E, suggest a suitable method of separating E from a mixture of X and E.
42. 5(a)2 marksWrite a balanced equation for the reaction between hydrochloric acid and limestone.
43. 5(b)3 marks5.0 g of CaCO3 is allowed to react completely with hydrochloric acid. Using the balanced equation in (a), calculate the mass of gas that would be produced. [Relative Atomic Mass: Ca = 40, O = 16, C = 12]
44. 5(c)1 markSuggest ONE way to verify the identity of the gas given off in (a).
45. 5(d)(i)2 marksWhat data must be collected if one wants to measure the rate of the reaction in (a) on page 14?
46. 5(d)(ii)3 marksSketch a labelled diagram to illustrate how the data collected in (d) (i) above may be represented.
47. 5(e)(i)2 marksState TWO ways in which the rate of a reaction could be increased.
48. 5(e)(ii)2 marksExplain how ONE of the ways stated in (e) (i) above causes an increase in reaction rate.