Quelpr
2 marksMole Concept

CSEC Chemistry · May/June 2009 · Paper 2 · Question 1(a)(iii)

Figure 2 shows thermometer readings for the highest temperature recorded for each addition of zinc to CuSO₄. The initial temperature in each case is 28°C.

Calculate the minimum mass of zinc required to completely react with 100 cm³ of 0.20 mol dm⁻³ copper(II) sulphate. Relative atomic mass of Zn = 65.

This question uses a figure or table from the paper — you'll see it when you practise.

The mark scheme is shown once you've answered.

Practise this question

Other parts of this question

  1. 1(a)(i)a)Describe what would be observed in the polystyrene cup in Figure 1.[2 marks]
  2. 1(a)(i)b)What does the observation you described in a) above indicate about the relative positions of zinc and copper in the reactivity series?[1 mark]
  3. 1(a)(i)c)Distinguish between an exothermic and an endothermic reaction.[2 marks]
  4. 1(a)(ii)a)Using the readings in Figure 2, complete Table 1 to show the final thermometer readings, and the changes in temperature.[2 marks]
  5. 1(a)(ii)b)On the graph paper provided on page 5, plot the temperature change (ΔT) against mass of zinc added.[3 marks]
  6. 1(a)(iii)c)From your graph, deduce the temperature change (ΔT) that will occur when 1.0 g of zinc is added to the copper(II) sulphate solution.[1 mark]
  7. 1(a)(iv)Use the information in (iii) above to explain why the different masses of zinc used in Experiments 4 and 5 give approximately the same change in temperature.[1 mark]
  8. 1(a)(v)Another group of students performs a similar experiment but uses silver instead of zinc. No temperature change is observed. Account for this observation.[2 marks]
  9. 1(b)(i)Complete Table 2 to show all of the possible inferences and write ionic equations where indicated.[2 marks]
  10. 1(b)(ii)Suggest a possible identity of the solid, R:[1 mark]
  11. 1(c)(i)Outline the procedure for the experiment.[2 marks]
  12. 1(c)(ii)List the materials necessary.[1 mark]
  13. 1(c)(iii)What evidence will result from your procedure to distinguish between the two acids?[1 mark]

More practice: the rest of this paper · more Mole Concept questions · all CSEC Chemistry past papers