Cambridge IGCSE · 0620 · Paper 3 · Theory (Core)

Chemistry 0620/33 Oct/Nov 2025 past paper

Cambridge IGCSE Chemistry (0620) Paper 3 (Theory (Core)), variant 3, Oct/Nov 2025: the question paper and its official mark scheme, 8 questions worth 80 marks, with the grade thresholds. Free to open, no account needed.

Questions: 8
Marks: 80
Grade A from: 40

Open the question paper Mark scheme

File names: 0620_w25_qp_33 · 0620_w25_ms_33

Grade thresholds for 0620/33 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
40	34	28	21	14

Topics in this paper

Which syllabus chapters 0620/33 Oct/Nov 2025 tested, by marks. Each chapter links to every past-paper question on it.

Chapter	Questions	Marks
The Periodic Table	2	22
Organic chemistry	1	17
Stoichiometry	2	16
Chemistry of the environment	1	11
Electrochemistry	1	8
Atoms, elements and compounds	1	6

Questions in 0620/33 Oct/Nov 2025

Question 1The Periodic Table · 4 marks
Fig. 1.1 shows part of the Periodic Table. Li I II III IV V VI VII VIII Na Ca Fe H Au Zn Al …
Question 2Atoms, elements and compounds · 6 marks
The symbol for an atom of xenon is shown. 131 54 Xe (a) Complete Table 2.1 to show the number of neutrons and nucleons in one atom of 131 54 Xe. Table 2.1 number of neutrons number of nucleons (b) …
Question 3Stoichiometry · 10 marks
(a) Table 3.1 shows the masses of ions, in mg, present in a 600 cm3 sample of contaminated water. Table 3.1 name of ion formula of ion mass of ion in 600 cm3 of contaminated water / mg calcium Ca2+ …
Question 4Organic chemistry · 17 marks
(a) Compound B is a molecule found in a plant called basil. Fig. 4.1 shows the displayed formula of a molecule of compound …
Question 5The Periodic Table · 18 marks
This question is about elements in different groups of the Periodic Table and their compounds. (a) Silicon is in Group IV of the Periodic Table. Explain why silicon is placed in Group IV. Give your answer in terms of electronic …
Question 6Chemistry of the environment · 11 marks
This question is about metals. (a) Iron is extracted from its ore using carbon in a blast furnace. When calcium carbonate is heated strongly in the blast furnace, it forms calcium oxide and carbon dioxide. CaCO3 CaO + CO2 (i) …
Question 7Electrochemistry · 8 marks
Fig. 7.1 shows the apparatus used to electroplate a nickel object with copper. power supply aqueous electrolyte nickel object Fig. 7.1 (a) Label the anode in Fig. 7.1. (b) Name a suitable aqueous electrolyte for the electroplating in Fig. 7.1. …
Question 8Stoichiometry · 6 marks
Excess dilute citric acid, C6H8O7, is added to aqueous sodium hydrogencarbonate to form aqueous sodium citrate, Na3C6H5O7, carbon dioxide and water. C6H8O7(aq) + 3NaHCO3(aq) Na3C6H5O7(aq) + 3CO2(g) …

Other Chemistry papers from Oct/Nov 2025

Questions students ask

Where can I get the 0620/33 Oct/Nov 2025 mark scheme?

Open the mark scheme above - it is the official Cambridge scheme for this exact paper (0620_w25_ms_33), and on a wide screen it sits beside the question you are reading.

What was the grade threshold for an A in 0620/33 Oct/Nov 2025?

40 marks out of 80, a C needed 28.

Which topics came up in 0620/33 Oct/Nov 2025?

Mostly The Periodic Table, Organic chemistry, Stoichiometry. The full list is in the table above.

Do I need an account to open 0620/33 Oct/Nov 2025?

No. Every paper opens for free without signing in. A free account also saves your pen marks and records your score against the grade thresholds.