Skip to content
Try on iPad

Chemistry of the d-block transition metals: WJEC A‑Level Chemistry questions

Every WJEC A-Level Chemistry exam question on 3.4 Chemistry of the d-block transition metals, 2016–2025, with its mark scheme and examiner’s report.

Find questions1,204
Calculations

1,204 questions

  1. Q6(a)

    Summer 2025 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2025 Unit 3, question 6(a): Give the observation(s) expected when aqueous sodium hydroxide is added gradually to aqueous chromium(III) chloride until the sodium hydroxide is in excess. [1]

  2. Q10(d)(i)

    Summer 2025 · Unit 3

    3 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2025 Unit 3, question 10(d)(i): Explain why these solutions are pale blue. [3]

  3. Q10(d)(ii)

    Summer 2025 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2025 Unit 3, question 10(d)(ii): Copper(I) compounds are often white solids. Give a reason why these compounds are not coloured. [1]

  4. Q10(d)(iii)

    Summer 2025 · Unit 3

    2 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2025 Unit 3, question 10(d)(iii): Many metal complexes change colour when a new ligand is added. The absorption spectra of two cobalt(II) complexes are given below. [CoCl4]2– [Co(H2O)6]2+ 0 25 0

  5. Q8(a)

    Summer 2024 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2024 Unit 3, question 8(a): State why transition elements can form a range of oxidation states in their compounds. [1]

  6. Q8(b)(i)

    Summer 2024 · Unit 3

    2 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2024 Unit 3, question 8(b)(i): Give a reason for your answer. [2]

  7. Q8(b)(ii)

    Summer 2024 · Unit 3

    3 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2024 Unit 3, question 8(b)(ii): In aqueous solutions, most vanadium ions form complexes with water acting as a ligand. I. Give the meaning of the term ligand. [1] II. Describe the bonding that

  8. Q10(c)(i)

    Summer 2024 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2024 Unit 3, question 10(c)(i): [1]

  9. Q10(c)(ii)

    Summer 2024 · Unit 3

    6 marks3.7 Entropy and feasibility of reactions3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2024 Unit 3, question 10(c)(ii): aqueous solution. [Cu(NH3)4(H2O)2]2+(aq) [Cu(cyclen)(H2O)2]2+(aq) + cyclen(aq) + 4NH3(aq) ΔHθ = +1.2 kJ mol–1 Measurements show that the strengths of the Cu―N b

  10. Q5

    Summer 2023 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2023 Unit 3, question 5: Addition of ammonia solution to aqueous copper(II) sulfate causes a pale blue precipitate to form followed by a coloured solution when excess ammonia solution i

  11. Q8(c)

    Summer 2023 · Unit 3

    2 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2023 Unit 3, question 8(c): Addition of aqueous sodium hydroxide to the solution of potassium dichromate causes a colour change. State the colour change and explain why this is not a redox

  12. Q12(c)

    Summer 2023 · Unit 3

    3 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2023 Unit 3, question 12(c): Explain the observations seen in experiment 3 Use these to name element X. [3]

  13. Q2

    Summer 2022 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 2: Addition of excess hydrochloric acid to aqueous copper(II) sulfate causes the solution to turn green. Give the formula of the copper-containing species present.

  14. Q9(a)

    Summer 2022 · Unit 3

    2 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 9(a): transition element. [2]

  15. Q9(b)

    Summer 2022 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 9(b): Explain why iron has more than one common oxidation state in its compounds. [1]

  16. Q9(c)

    Summer 2022 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 9(c): Draw the structure of the [Fe(H2O)6]3+ ion. [1]

  17. Q9(d)(i)

    Summer 2022 · Unit 3

    2 marks3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 9(d)(i): same colour. [2]

  18. Q9(d)(ii)

    Summer 2022 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 9(d)(ii): Suggest how you would select an appropriate wavelength to find the concentration of [Fe(H2O)6]3+ in the equilibrium mixture. [1]

  19. Q9(e)(i)

    Summer 2022 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2022 Unit 3, question 9(e)(i): Give the formula of the precipitate and its colour. [1] Formula Colour

  20. Q8

    Summer 2019 · Unit 3

    1 mark3.4 Chemistry of the d-block transition metals
    The whole paper ↗
    Summer 2019 Unit 3, question 8: Draw the structure of the copper-containing ion formed when concentrated hydrochloric acid is added to a solution containing [Cu(H2O)6]2+ ions. [1]
All 34 questions on Chemistry of the d-block transition metals, as a list
  1. Summer 2025, Unit 3, Q6(a) (1 mark): Give the observation(s) expected when aqueous sodium hydroxide is added gradually to aqueous chromium(III) chloride until the sodium hydroxide is in excess. [1]
  2. Summer 2025, Unit 3, Q10(d)(i) (3 marks): Explain why these solutions are pale blue. [3]
  3. Summer 2025, Unit 3, Q10(d)(ii) (1 mark): Copper(I) compounds are often white solids. Give a reason why these compounds are not coloured. [1]
  4. Summer 2025, Unit 3, Q10(d)(iii) (2 marks): Many metal complexes change colour when a new ligand is added. The absorption spectra of two cobalt(II) complexes are given below. [CoCl4]2– [Co(H2O)6]2+ 0 25 0
  5. Summer 2024, Unit 3, Q8(a) (1 mark): State why transition elements can form a range of oxidation states in their compounds. [1]
  6. Summer 2024, Unit 3, Q8(b)(i) (2 marks): Give a reason for your answer. [2]
  7. Summer 2024, Unit 3, Q8(b)(ii) (3 marks): In aqueous solutions, most vanadium ions form complexes with water acting as a ligand. I. Give the meaning of the term ligand. [1] II. Describe the bonding that
  8. Summer 2024, Unit 3, Q10(c)(i) (1 mark): [1]
  9. Summer 2024, Unit 3, Q10(c)(ii) (6 marks): aqueous solution. [Cu(NH3)4(H2O)2]2+(aq) [Cu(cyclen)(H2O)2]2+(aq) + cyclen(aq) + 4NH3(aq) ΔHθ = +1.2 kJ mol–1 Measurements show that the strengths of the Cu―N b
  10. Summer 2023, Unit 3, Q5 (1 mark): Addition of ammonia solution to aqueous copper(II) sulfate causes a pale blue precipitate to form followed by a coloured solution when excess ammonia solution i
  11. Summer 2023, Unit 3, Q8(c) (2 marks): Addition of aqueous sodium hydroxide to the solution of potassium dichromate causes a colour change. State the colour change and explain why this is not a redox
  12. Summer 2023, Unit 3, Q12(c) (3 marks): Explain the observations seen in experiment 3 Use these to name element X. [3]
  13. Summer 2022, Unit 3, Q2 (1 mark): Addition of excess hydrochloric acid to aqueous copper(II) sulfate causes the solution to turn green. Give the formula of the copper-containing species present.
  14. Summer 2022, Unit 3, Q9(a) (2 marks): transition element. [2]
  15. Summer 2022, Unit 3, Q9(b) (1 mark): Explain why iron has more than one common oxidation state in its compounds. [1]
  16. Summer 2022, Unit 3, Q9(c) (1 mark): Draw the structure of the [Fe(H2O)6]3+ ion. [1]
  17. Summer 2022, Unit 3, Q9(d)(i) (2 marks): same colour. [2]
  18. Summer 2022, Unit 3, Q9(d)(ii) (1 mark): Suggest how you would select an appropriate wavelength to find the concentration of [Fe(H2O)6]3+ in the equilibrium mixture. [1]
  19. Summer 2022, Unit 3, Q9(e)(i) (1 mark): Give the formula of the precipitate and its colour. [1] Formula Colour
  20. Summer 2019, Unit 3, Q8 (1 mark): Draw the structure of the copper-containing ion formed when concentrated hydrochloric acid is added to a solution containing [Cu(H2O)6]2+ ions. [1]
  21. Summer 2019, Unit 3, Q10(c)(i) (3 marks): It is an example of a homogeneous catalyst. I. State what is meant by a homogeneous catalyst. [1] Explain why transition metal complexes such as [Ir(CO)2I2]– ca
  22. Summer 2019, Unit 3, Q12(a)(iii) (2 marks): Give the colours of the precipitates formed when sodium hydroxide solution is added to solutions containing the following ions. [2] Mg2+(aq) Fe2+(aq) Cr3+(aq) P
  23. Summer 2019, Unit 3, Q12(a)(iv) (3 marks): The method given opposite is incomplete. Suggest an additional step that would allow the remaining solutions formed in step 2 to be identified. Give the expecte
  24. Summer 2018, Unit 3, Q2 (1 mark): Excess sodium hydroxide is added to an aqueous solution of chromium(III) chloride, CrCl3. Give the formula of the chromium-containing ion formed. [1]
  25. Summer 2018, Unit 3, Q9(a) (2 marks): [2]
  26. Summer 2018, Unit 3, Q9(b) (3 marks): [3]
  27. Summer 2018, Unit 3, Q9(c) (4 marks): Upon addition of hydrochloric acid the solution turned blue as [CoCl4]2– ions formed according to the equilibrium shown below. [Co(H2O)6]2+ + 4Cl– a [CoCl4]2– +
  28. Summer 2018, Unit 3, Q9(d)(i) (3 marks): 518 nm. Calculate the energy of this absorbance in kJ mol–1. [3] Energy = kJ mol–1
  29. Summer 2018, Unit 3, Q9(d)(ii) (1 mark): A colorimeter was used to study the equilibrium between the two ions. Suggest, giving a reason, an appropriate wavelength to use for the experiment. [1]
  30. Summer 2018, Unit 3, Q12(b) (6 marks): A student was provided with five ionic solids containing familiar cations and anions. Each solid contains a different cation. The solids were labelled A, B, C,
  31. Summer 2017, Unit 3, Q2 (1 mark): Give an example of a transition metal used as a catalyst. You should name the metal and identify the reaction it catalyses. [1]
  32. Summer 2017, Unit 3, Q12(a) (3 marks): The diagram below shows some reactions of copper(II) ions in solution. addition of solution B pale blue royal blue solution precipitate A C addition of NaOH(aq)
  33. Summer 2017, Unit 3, Q12(b) (1 mark): Vanadium exhibits the properties of a typical transition element, such as having variable oxidation states and forming coloured complexes. Explain why transitio
  34. Summer 2017, Unit 3, Q12(f) (3 marks): to colourless Ce3+. A titration using this reaction does not usually include an indicator and colorimetry is sometimes used. State why an indicator may not be u

Questions, mark schemes and examiner’s reports are © WJEC CBAC Ltd, from their published past papers. Plumi isn’t affiliated with any exam board. Want whole papers? Every WJEC A-Level Chemistry paper.

Rather write your answers by hand on iPad? Plumi marks them against the same mark schemes.