CSEC Chemistry · January 2020 · 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)1 markDefine the term 'rate of reaction'.
2. 1(b)(i)5 marksFrom the gas syringes displayed in Figure 1 on page 5, record the volume of gas produced in the appropriate spaces in Table 1. The volume at times 0, 5 and 6 minutes have already been recorded.
3. 1(b)(ii)5 marksUse the data in Table 1 to plot a graph of the volume of gas produced against time, using the axes below.
4. 1(b)(iii)1 markFrom your graph, determine the time taken for the reaction to be completed.
5. 1(b)(iv)1 markDuring which time interval was the rate of reaction fastest?
6. 1(b)(v)3 marksExplain your answer in (b) (iv).
7. 1(b)(vi)1 markFrom your graph, determine the volume of gas produced at 2.5 minutes.
8. 1(b)(vii)3 marksUse your answer in (b) (vi) to determine the number of moles of gas produced at 2.5 minutes. [one mole of gas occupies 22.4 dm³ at standard temperature and pressure.]
9. 1(b)(viii)1 markAndrew wanted to identify the gas produced. He placed a lighted splint in a sample of the gas, which extinguished with a 'squeaky pop'. Deduce the identity of the gas.
10. 1(c)(i)1 markAndrew's second experiment required the use of the same mass of magnesium but in the powdered form instead of strips. State the factor that Andrew is now investigating.
11. 1(c)(ii)2 marksWrite a balanced chemical equation with state symbols for the reaction that occurred between magnesium and sulfuric acid in the experiments.
12. 1(c)(iii)1 markState ONE factor, other than the factor investigated by Andrew, which can affect the rate of a reaction.
13. 2(a)(i)1 markDefine 'reduction' in terms of oxidation states.
14. 2(a)(ii)1 markDeduce the oxidation state of Cu in CuI.
15. 2(a)(iii)2 marksDefine the term 'oxidizing agent'.
16. 2(a)(iv)2 marksWith reference to the equation above, state, with a reason, which substance is acting as an oxidizing agent.
17. 2(a)(v)1 markSolution A was added to a small portion of an aqueous solution of potassium iodide in a test tube. The colourless potassium iodide turned brown. State whether Solution A contained an oxidizing agent or a reducing agent.
18. 2(a)(vi)2 marksExplain your answer in (a) (v).
19. 2(a)(vii)2 marksWrite a balanced chemical equation to show the formation of the brown product in the reaction in (a) (v).
20. 2(b)2 marksDescribe what is observed with regard to the chemical reaction that occurs in the test tube.
21. 2(c)2 marksOne of the substances in the equation in (b) on page 11, is acting as a reducing agent. Describe a simple laboratory test that could be used to identify a reducing agent.
22. 3(a)3 marksList THREE characteristics of a homologous series.
23. 3(b)(i)2 marksDraw the FULLY displayed structural formula for Compound A which has the molecular formula C₂H₄.
24. 3(b)(ii)1 markState the homologous series to which Compound A belongs.
25. 3(b)(iii)1 markWrite the molecular formula for the compound which has five carbon atoms of the homologous series stated in (b) (ii).
26. 3(c)(i)2 marksDraw the FULLY displayed structural formula for Compound B which has the molecular formula C₂H₆.
27. 3(c)(ii)1 markState the homologous series to which Compound B belongs.
28. 3(c)(iii)1 markWrite the molecular formula for the compound which has five carbon atoms of the homologous series stated in (c) (ii).
29. 3(d)(i)2 marksFor EACH of the following homologous series write the general formula: Carboxylic acid, Alcohol.
30. 3(d)(ii)2 marksFor EACH of the following homologous series write the name of the first member: Carboxylic acid, Alcohol.
31. 4(a)(i)2 marksIdentify TWO ions present in the electrolyte and include their state symbols.
32. 4(a)(ii)2 marksState TWO factors that affect the discharge of an ion in the electrolyte during electrolysis.
33. 4(a)(iii)2 marksPredict which ions present in the electrolyte will be attracted towards the anode.
34. 4(a)(iv)2 marksWrite a balanced equation for the reaction at the anode.
35. 4(a)(v)2 marksWrite a balanced equation for the reaction at the cathode.
36. 4(b)3 marksState whether EACH of the substances given in Table 2 are classified as conductors or non-conductors.
37. 4(c)2 marksCarbon is an example of a non-metal. State TWO uses of carbon.
38. 5(a)(i)2 marksState the name of Compound C and the homologous series to which it belongs.
39. 5(a)(ii)2 marksDraw the FULLY displayed structural formulae of the two molecules that are produced when Compound C is hydrolysed.
40. 5(b)(i)3 marksState the name of Compound D and identify the reagent and conditions necessary for ethanol to be converted into Compound D.
41. 5(b)(ii)7 marksExplain how ethanol can be made from the fermentation of sugar. Include the chemical equation for the overall fermentation process.
42. 5(b)(iii)1 markState ONE other use of ethanol.
43. 6(a)(i)2 marksState the TWO conditions necessary for the corrosion of a metal.
44. 6(a)(ii)6 marksState whether corrosion will occur for EACH of the test tubes shown in Figure 2. Give ONE reason to support your answer in EACH case. Test tube A, Test tube B, Test tube C.
45. 6(a)(iii)1 markSuggest the reason why the boiled water was covered with oil in Test tube B.
46. 6(b)(i)2 marksState ONE alloy of aluminium and its use.
47. 6(b)(ii)2 marksExplain why the corrosion of aluminium is beneficial.
48. 6(b)(iii)2 marksWrite a balanced equation to show the product formed when aluminium is left exposed to air.