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Redox past paper questions

O Level Chemistry 5070 · Chemical reactions. 1 Use a Roman numeral to indicate the oxidation number of an element in a compound 2 Define redox reactions as involving simultaneous reduction and oxidation 3 Define oxidation in terms of: (a) gain of oxygen (b) loss of electrons (c) an increase in oxidation number 4 Define reduction in terms of: (a) loss of oxygen (b) gain of electrons (c) a decrease in oxidation number 5 Identify redox reactions as reactions involving gain and loss of oxygen, or gain and loss of electrons 6 Identify redox reactions by changes in oxidation number using: (a) the oxidation number of elements in their uncombined state is zero (b) the oxidation number of a monatomic ion is the same as the charge on the ion (c) the sum of the oxidation numbers in a compound is zero (d) the sum of the oxidation numbers in an ion is equal to the charge on the ion 7 Identify redox reactions by the colour changes involved when

It came up in 46 of 72 papers, for about 2 marks a paper when it does. It last came up in October/November 2025.

Often set with Identification of ions and gases, The mole and the Avogadro constant, Formulae, Rate of reaction.

74 questions, newest first

  1. 5070/12/O/N/25 Question 18 · 1 mark
  2. 5070/22/O/N/25 Question 6 part (c) · 2 marks
  3. 5070/21/M/J/25 Question 1 part (d) · 1 mark
  4. 5070/21/M/J/25 Question 5 part (c(i)) · 2 marks
  5. 5070/21/M/J/25 Question 6 parts (c(i)) (c(ii)) · 3 marks
  6. 5070/22/M/J/25 Question 1 part (c) · 1 mark
  7. 5070/22/M/J/25 Question 6 parts (c(i)) (c(ii)) · 3 marks
  8. 5070/11/O/N/24 Question 18 · 1 mark
  9. 5070/12/O/N/24 Question 20 · 1 mark
  10. 5070/21/O/N/24 Question 2 part (a(i)) · 1 mark
  11. 5070/21/O/N/24 Question 5 part (d(ii)) · 1 mark
  12. 5070/22/O/N/24 Question 6 parts (d(i)) (d(ii)) · 2 marks
  13. 5070/11/M/J/24 Question 21 · 1 mark
  14. 5070/11/M/J/24 Question 22 · 1 mark
  15. 5070/12/M/J/24 Question 20 · 1 mark
  16. 5070/21/M/J/24 Question 4 parts (d) (e) · 4 marks
  17. 5070/22/M/J/24 Question 4 parts (d(i)) (d(ii)) (e) · 4 marks
  18. 5070/11/O/N/23 Question 19 · 1 mark
  19. 5070/12/O/N/23 Question 18 · 1 mark
  20. 5070/21/O/N/23 Question 4 parts (d(i)) (d(ii)) · 2 marks
  21. 5070/22/O/N/23 Question 4 parts (d(i)) (d(ii)) · 2 marks
  22. 5070/11/M/J/23 Question 17 · 1 mark
  23. 5070/11/M/J/23 Question 18 · 1 mark
  24. 5070/12/M/J/23 Question 19 · 1 mark
  25. 5070/12/M/J/23 Question 20 · 1 mark
  26. 5070/21/M/J/23 Question 1 part (d) · 1 mark
  27. 5070/21/M/J/23 Question 2 parts (b(i)) (b(ii)) · 2 marks
  28. 5070/22/M/J/23 Question 1 parts (e) (f) · 2 marks
  29. 5070/22/M/J/23 Question 2 parts (b(i)) (b(ii)) · 2 marks
  30. 5070/42/M/J/23 Question 3 part (a(ii)) · 2 marks
  31. 5070/11/O/N/22 Question 23 · 1 mark
  32. 5070/11/O/N/22 Question 24 · 1 mark
  33. 5070/11/O/N/22 Question 25 · 1 mark
  34. 5070/12/O/N/22 Question 24 · 1 mark
  35. 5070/12/O/N/22 Question 25 · 1 mark
  36. 5070/21/O/N/22 Question 5 part (a) · 2 marks
  37. 5070/22/O/N/22 Question 5 part (a) · 2 marks
  38. 5070/11/M/J/22 Question 23 · 1 mark
  39. 5070/11/M/J/22 Question 24 · 1 mark
  40. 5070/12/M/J/22 Question 23 · 1 mark
  41. 5070/12/M/J/22 Question 24 · 1 mark
  42. 5070/21/M/J/22 Question 1 part (f) · 1 mark
  43. 5070/21/M/J/22 Question 6 part (b(i)) · 2 marks
  44. 5070/22/M/J/22 Question 1 part (f) · 1 mark
  45. 5070/22/M/J/22 Question 7 part (d(i)) · 1 mark
  46. 5070/11/O/N/21 Question 19 · 1 mark
  47. 5070/11/O/N/21 Question 20 · 1 mark
  48. 5070/21/O/N/21 Question 2 part (e(i)) · 1 mark
  49. 5070/21/O/N/21 Question 3 part (d) · 2 marks
  50. 5070/21/O/N/21 Question 5 part (a) · 1 mark
  51. 5070/22/O/N/21 Question 3 part (d) · 2 marks
  52. 5070/22/O/N/21 Question 5 part (a) · 2 marks
  53. 5070/42/O/N/21 Question 4 part (e) · 1 mark
  54. 5070/11/M/J/21 Question 20 · 1 mark
  55. 5070/12/M/J/21 Question 20 · 1 mark
  56. 5070/21/M/J/21 Question 4 parts (d(i)) (d(ii)) · 2 marks
  57. 5070/21/M/J/21 Question 7 part (d(ii)) · 1 mark
  58. 5070/22/M/J/21 Question 3 part (b(iv)) · 1 mark
  59. 5070/22/M/J/21 Question 4 parts (c(i)) (c(ii)) · 2 marks
  60. 5070/11/O/N/20 Question 21 · 1 mark
  61. 5070/12/O/N/20 Question 21 · 1 mark
  62. 5070/21/O/N/20 Question 5 part (d(ii)) · 1 mark
  63. 5070/21/O/N/20 Question 7 part (b(i)) · 1 mark
  64. 5070/21/O/N/20 Question 9 part (a) · 2 marks
  65. 5070/22/O/N/20 Question 3 part (b(ii)) · 1 mark
  66. 5070/22/O/N/20 Question 7 part (c(i)) · 1 mark
  67. 5070/22/O/N/20 Question 9 part (b(i)) · 2 marks
  68. 5070/11/M/J/20 Question 18 · 1 mark
  69. 5070/12/M/J/20 Question 19 · 1 mark
  70. 5070/21/M/J/20 Question 2 part (d) · 1 mark
  71. 5070/21/M/J/20 Question 9 part (c(i)) · 1 mark
  72. 5070/22/M/J/20 Question 4 part (d) · 1 mark
  73. 5070/22/M/J/20 Question 8 part (b) · 1 mark
  74. 5070/42/M/J/20 Question 1 part (b(ii)) · 1 mark

More in Chemical reactions: Physical and chemical changes, Rate of reaction, Reversible reactions and equilibrium.

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