Cambridge O Level · 5070 · Paper 2 · Theory
Chemistry 5070/21 Oct/Nov 2025 past paper
Cambridge O Level Chemistry (5070) Paper 2 (Theory), variant 1, Oct/Nov 2025: the question paper and its official mark scheme, 10 questions worth 80 marks, with the grade thresholds. Free to open, no account needed.
- Questions
- 10
- Marks
- 80
- Grade A from
- 57
File names: 5070_w25_qp_21 · 5070_w25_ms_21
Grade thresholds for 5070/21 Oct/Nov 2025
The minimum raw marks Cambridge set for each grade on this component (out of 80). Thresholds change every session and variant, so always compare your score with the paper you actually sat.
| A | B | C | D | E |
|---|---|---|---|---|
| 57 | 41 | 24 | 18 | 12 |
Topics in this paper
Which syllabus chapters 5070/21 Oct/Nov 2025 tested, by marks. Each chapter links to every past-paper question on it.
| Chapter | Questions | Marks |
|---|---|---|
| Organic chemistry | 3 | 26 |
| Atoms, elements and compounds | 2 | 13 |
| Chemistry of the environment | 2 | 12 |
| Stoichiometry | 1 | 10 |
| Electrochemistry | 1 | 10 |
| States of matter | 1 | 9 |
Questions in 5070/21 Oct/Nov 2025
- Question 1
Choose from the following compounds to answer the questions. compound A CH3OH compound B CH3—CH2OH compound C compound D CH3—CH=CH2 compound E CH3—CH2—COOCH3 compound F CH3—CH2—CH2—CH2—COOH compound G CH3—CH=CH—COOCH3 Each compound can be used once, more than once or not …
- Question 2
A sample of sulfur found on the planet Mars contains four isotopes. Table 2.1 shows the percentage abundances of these four isotopes. Table 2.1 isotope percentage abundance …
- Question 3
Sodium hydrogencarbonate decomposes when heated. 2NaHCO3(s) Na2CO3(s) …
- Question 4
Fluorine, chlorine, bromine and iodine are elements in Group VII. (a) Bromine has a low boiling point. It is a liquid at room temperature. (i) Describe the arrangement and motion of molecules in liquid bromine. (ii) Explain why bromine has …
- Question 5
Nickel is a transition element. (a) Nickel has good electrical conductivity and good thermal conductivity. Nickel is also ductile and malleable. State two other physical properties of nickel that are typical of a transition element. …
- Question 6
This question is about an unsaturated hydrocarbon called ethyne. Fig. 6.1 shows the displayed formula of ethyne. …
- Question 7
Ethene is used to make ethanol and poly(ethene). Fig. 7.1 shows the displayed formula of ethene. …
- Question 8
Petroleum is a mixture of hydrocarbons most of which are alkanes. Table 8.1 shows some of the unbranched alkanes present in petroleum and the number of carbon atoms in one molecule of the alkane. Table 8.1 name number of carbon …
- Question 9
Anhydrous copper(II) sulfate is a white solid. (a) State the meaning of the term anhydrous. (b) Anhydrous copper(II) sulfate is added to water. State the colour of the solution formed. (c) Aqueous ammonia is added dropwise until in excess to …
- Question 10
Air is a mixture of gases. (a) State the percentage by volume of oxygen in clean, dry air. (b) The percentage of carbon dioxide in air is increasing. (i) State one adverse effect of this increasing percentage of carbon dioxide. …
Other Chemistry papers from Oct/Nov 2025
- 5070/11 Multiple choice
- 5070/12 Multiple choice
- 5070/22 Theory
- 5070/41 Alternative to Practical
- 5070/42 Alternative to Practical