Quelpr

CSEC Chemistry · May/June 2013 · Paper 2

44 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.

Practise this paper
  1. 1(a)(i)2 marksFor EACH temperature in Table 1, calculate the mass of potassium iodide that was dissolved in the beaker of water, and record the value in the space provided.
  2. 1(a)(ii)3 marksOn Figure 1, plot mass of salt dissolved (solubility) against temperature, and draw a straight line through the points.
  3. 1(a)(iii)1 markFrom the graph, determine the solubility (in grams per 100 cm³) of potassium iodide at 70 °C.
  4. 1(a)(iv)2 marks100 cm³ of distilled water is saturated with potassium iodide at 70 °C. Calculate the mass of potassium iodide that will be precipitated out from solution, if this solution is then cooled down to 30 °C.
  5. 1(a)(v)3 marksCalculate the concentration (mol dm⁻³) of a saturated solution of potassium iodide at 30 °C. (RAM: K = 39, I = 127).
  6. 1(b)4 marksExplain why the statement above is true.
  7. 1(c)(i)1 markA suggested list of apparatus and chemicals which you will use in obtaining the pure solid sample of EITHER of the two salts.
  8. 1(c)(ii)3 marksAn outline of the steps for the procedure to be used.
  9. 1(c)(iii)2 marksList the MAIN observations that will be expected at EACH stage of the experiment.
  10. 1(d)4 marksComplete the table by inserting the appropriate inferences.
  11. 2(a)(i)3 marksComparison of Mg and X according to ease of ionization
  12. 2(a)(ii)3 marksComparison of Cl and Y according to strength of oxidizing power
  13. 2(b)(i)1 markSimilar physical property
  14. 2(b)(ii)1 markDifferent physical property
  15. 2(c)(i)1 markState the type of bonding that occurs between phosphorous and Element Y.
  16. 2(c)(ii)3 marksReferring to only the electrons in the outer shells of the elements, sketch a diagram to show the bonding between phosphorous and Y.
  17. 2(c)(iii)3 marksWrite the chemical formula for the compound formed from phosphorous and Y. Suggest TWO properties of this compound.
  18. 3(a)2 marksExplain what is meant by the term 'cracking'.
  19. 3(b)(i)1 markDraw a structural representation of glucose.
  20. 3(b)(ii)2 marksUse THREE units of glucose (monomer from Part (b) (i)) to show how the monomers are linked together in a partial structure of starch.
  21. 3(b)(iii)1 markState the type of polymerization reaction that glucose undergoes to form starch, and the name of the family of polymers to which starch belongs.
  22. 3(c)(i)2 marksDescribe how the structure of the protein is affected by acid hydrolysis.
  23. 3(c)(ii)2 marksDraw the structure of the monomer unit that results from the acid hydrolysis of the structure shown in Figure 3.
  24. 3(d)(i)a)2 marksIdentify TWO monomers that will undergo condensation polymerization
  25. 3(d)(i)b)1 markIdentify ONE monomer that will undergo addition polymerization.
  26. 3(d)(ii)1 markState the name of the family of polymers that will be formed when monomers P and R react together.
  27. 4(a)4 marksState FOUR factors that can influence the rate of reaction.
  28. 4(b)(i)1 markUse the graph in Figure 4 to determine the total volume of CO₂ produced.
  29. 4(b)(ii)2 marksCalculate the mass of CaCO₃ used in the experiment. [RAM: Ca = 40, C = 12, O = 16]
  30. 4(b)(iii)2 marksOne of the students suggested that powdered calcium carbonate should have been used instead of chips. State, with reason, how the time for completion of the experiment would have been affected.
  31. 4(c)(i)2 marksExplain why metals are often combined to make alloys.
  32. 4(c)(ii)4 marksOther than electrolysis, describe a suitable laboratory procedure that could be used to obtain a sample of dry copper from a sample of the alloy.
  33. 5(a)(i)2 marksthe name of the electrolyte and ions present
  34. 5(a)(ii)2 marksan explanation for which ions are preferentially discharged at the electrodes
  35. 5(a)(iii)4 marksionic equations showing the reactions at EACH electrode
  36. 5(a)(iv)1 markthe role of the ion exchange membrane in the diagram.
  37. 5(b)(i)1 markState what is expected to happen to the anode during the experiment.
  38. 5(b)(ii)5 marksCalculate the mass of pure copper that would be produced during the experiment if a current of 5 A flowed for 30 minutes. (Molar mass of Cu: 64 g mol⁻¹)
  39. 6(a)(i)2 marksname the MAIN pollutant responsible
  40. 6(a)(ii)4 marksstate TWO harmful effects.
  41. 6(b)(i)2 marksWater use
  42. 6(b)(ii)2 marksGarbage disposal
  43. 6(b)(iii)2 marksEnergy use
  44. 6(c)3 marksState your opinion (position) on this statement and provide TWO points to justify your position.

More CSEC Chemistry papers