Quelpr

CAPE Chemistry Unit 1 · May/June 2025 · Paper 2

35 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 marksState TWO factors which influence the values of the first ionization energy.
  2. 1(a)(ii)4 marksExplain how the ionization energy data provides evidence for the idea of subshells, using appropriate elements from the sketch in Figure 1.
  3. 1(b)(i)1 markComplete Table 1 by calculating the values of Log10 IE (Ionization Energy).
  4. 1(b)(ii)2 marksUse the data in Table 1 to plot a graph on page 7, of Log10 IE (Ionization Energy) against number of electrons removed. The first point has been plotted in Figure 2.
  5. 1(b)(iii)3 marksExplain the shape of the graph.
  6. 1(b)(iv)1 markState the electronic configuration of Element D, based on the shape of the graph.
  7. 1(c)(i)4 marksOutline fully the steps involved in the procedure that the student would follow in order to obtain the melting point of Substance S.
  8. 1(c)(ii)1 markBased on the melting point data obtained, the student concludes that S is a covalent compound. Further analysis reveals that it is nonpolar. State whether Substance S will dissolve in water or tetrachloromethane.
  9. 1(c)(iii)2 marksIt was determined that Substance S is a solid with a low melting point. Describe the type of forces of attraction that exist between the molecules of Substance S.
  10. 1(d)(i)2 marksExplain the change from a solid to a liquid state using kinetic theory.
  11. 1(d)(ii)2 marksExplain the nature of the liquid state using kinetic theory.
  12. 1(d)(iii)2 marksExplain the change from liquid to the gaseous state using kinetic theory.
  13. 1(e)(i)3 marksCalculate the molar mass of the liquid. [R = 8.314 J K^-1 mol^-1.]
  14. 1(e)(ii)1 markSuggest which measurement used in the calculation of the molar mass is subject to the greatest error.
  15. 2(a)(i)4 marksDescribe the FOUR characteristic features of this dynamic equilibrium.
  16. 2(a)(ii)2 marksWrite a balanced chemical equation to represent the reaction described in 2(a) above.
  17. 2(a)(iii)3 marksCalculate the Kp value of the equilibrium mixture.
  18. 2(b)(i)4 marksDescribe EACH of the following terms: Solubility product [2 marks] Common ion effect [2 marks]
  19. 2(b)(ii)3 marksCalcium phosphate, Ca3(PO4)2, is a water-insoluble mineral used to make commercial fertilizers. Given that the concentrations of Ca2+ and PO4^3- ions in equilibrium are 2 × 10^-8 and 1 × 10^-9 respectively, determine…
  20. 2(b)(iii)2 marksWrite a balanced equation for the equilibrium reaction of the formation of calcium and phosphate ions from calcium phosphate.
  21. 2(c)2 marksComment on the solubility of silver chloride in water compared with the solubility of silver chloride in dilute hydrochloric acid and justify the difference, if any.
  22. 2(d)5 marksWrite the steps in an experimental procedure for the determination of the solubility product constant of barium hydroxide, Ba(OH)2.
  23. 2(e)(i)1 markDefine the term 'buffer solution'.
  24. 2(e)(ii)3 marksExplain how the molecular structure of amino acids relates to their function as buffer solutions in human blood.
  25. 2(e)(iii)1 markState ONE industry in which buffer solutions are used.
  26. 3(a)(i)4 marksDescribe the trend in EACH of the following: Electrical conductivity from silicon to lead [2 marks] The melting point from silicon to lead [2 marks]
  27. 3(a)(ii)4 marksAccount for the variation in melting points from C(d) to Sn, in terms of structure and bonding.
  28. 3(b)(i)1 markDescribe the reaction of lead (IV) chloride with water.
  29. 3(b)(ii)2 marksWrite a balanced equation for the reaction described in (b)(i).
  30. 3(c)(i)2 marksState the trend in EACH of the following from beryllium to barium: Density [1 mark] Atomic radii [1 mark]
  31. 3(c)(ii)3 marksAccount for the trend in the atomic radii in terms of the nuclear charge and the screening effect.
  32. 3(d)(i)4 marksComplete the table below by recording the observations that would be made when a 1 molar (M) solution of sodium sulfate is added to 0.1 mol dm^-3 of each of the Group II cations (Mg2+, Ca2+, Sr2+, Ba2+).
  33. 3(d)(ii)4 marksAccount for the observations in (d)(i).
  34. 3(d)(iii)2 marksWrite the ionic equation for the reaction between the barium ion, Ba2+ and the 1 M sodium sulfate solution.
  35. 3(e)4 marksFor any TWO of the metals, complete the following table by naming ONE compound of the metal and the use of the compound.

More CAPE Chemistry Unit 1 papers