CAPE Chemistry Unit 1 · May/June 2026 · Paper 2

33 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 markDefine mass number.
2. 1(a)(ii)1 markDefine isotopes.
3. 1(b)3 marksElement X has five naturally occurring isotopes as given in Table 1. Calculate the relative atomic mass of Element X.
4. 1(c)(i)1 markDefine mole of a substance.
5. 1(c)(ii)1 markDefine molar mass.
6. 1(d)(i)4 marksCalculate the empirical formula of the product of the reaction between 10.0 g of lithium and excess oxygen that gave 21.5 g of lithium oxide.
7. 1(d)(ii)2 marksState TWO postulates of Dalton's atomic theory that are highlighted by the reaction and associated calculations in (d)(i).
8. 1(e)(i)4 marksCompare bonding in N2 and CaO in terms of electron interaction and polarity.
9. 1(e)(ii)2 marksState the TWO types of intra-molecular bonds present in the NH4+ structure.
10. 1(f)4 marksThe boiling point of HCl is -85 °C whereas the boiling point of HF is 20 °C. With reference to the electronegativity of the halogen, explain the difference in the boiling point temperatures of HCl and HF.
11. 1(g)2 marksCalculate the volume of 4.10 g of Ar at STP. [1 mole of gas occupies 22.4 dm³ at STP.]
12. 1(h)5 marksOutline the experimental steps that can be used to determine the volume of a 0.1152 M solution of H2SO4 which would be required to neutralize 25.00 mL of a 0.1913 M KOH solution.
13. 2(a)2 marksDefine the term 'rate of a reaction'.
14. 2(b)(i)4 marksWith reference to the experiment number used, deduce the order of the reaction with respect to Substance A and Substance B.
15. 2(b)(ii)1 markWrite the rate equation for the reaction between A and B.
16. 2(b)(iii)2 marksUsing the rate equation from (b)(ii), calculate the numerical value of the rate constant k, stating its unit.
17. 2(b)(iv)2 marksUsing the rate equation from (b)(ii), suggest a mechanism for the reaction between A and B.
18. 2(c)1 markDefine the term 'acid' using the Bronsted-Lowry theory.
19. 2(d)(i)2 marksWrite the equation for the dissociation of hydrofluoric acid in aqueous solution.
20. 2(d)(ii)1 markWrite the expression for the dissociation constant for hydrofluoric acid.
21. 2(d)(iii)3 marksCalculate the pH of 0.10 mol dm^-3 hydrofluoric acid.
22. 2(d)(iv)3 marksA student performs a titration, adding 0.10 mol dm^-3 sulfuric acid to 25 cm³ of 0.10 mol dm^-3 sodium hydroxide solution. Using the axes in Figure 1, sketch a graph to show the changes in pH which occur during the…
23. 2(e)(i)2 marksDefine standard cell potential.
24. 2(e)(ii)2 marksDefine standard electrode potential.
25. 2(f)5 marksDescribe, in detail, the steps that could be used to determine the standard electrode potential of copper in the laboratory.
26. 3(a)(i)4 marksList FOUR properties of transition metals.
27. 3(a)(ii)4 marksExplain the relatively small changes which occur across the series of transition elements in the first ionization energy, Delta H_1E, shown in Table 3.
28. 3(a)(iii)3 marksCompare the atomic radius of calcium with those of the transition elements.
29. 3(a)(iv)2 marksWrite the electronic configuration of Cu and Cu2+.
30. 3(b)(i)4 marksDescribe the reaction of chlorine with hydrogen and write a balanced chemical equation for the reaction.
31. 3(b)(ii)4 marksDescribe the reaction of bromine with hydrogen and write a balanced chemical equation for the reaction.
32. 3(b)(iii)4 marksWith reference to the bond energies of the hydrides given in Table 4, explain the relative thermal stabilities of the hydrogen halides.
33. 3(c)5 marksComplete Table 5 by writing the observations based on the deductions written for the cation and anion in Compound S.