The Most-Tested IGCSE Chemistry (0620) Topics — We Analysed 17,000+ Past-Paper Questions
Which IGCSE Chemistry topics come up most? We analysed 17,492 real past-paper questions from our Cambridge IGCSE Chemistry (0620) library — our largest dataset yet — and tagged every one to its syllabus topic. The result shows exactly where to aim your revision. Here's the data.
The most-tested IGCSE Chemistry chapters
IGCSE Chemistry 0620 — questions by chapter
Share of 17,492 past-paper questions · PapaMarks
Source: analysis of 17,492 IGCSE Chemistry 0620 past-paper questions · papamarks.com
3 things the data tells you
The 10 most-tested individual topics
| # | Topic | Share of questions |
|---|---|---|
| 1 | Properties of Acids & Bases | 3.5% |
| 2 | Air | 3.3% |
| 3 | Writing Equations | 2.8% |
| 4 | Atomic Structure | 2.3% |
| 5 | Fossil Fuels | 2.1% |
| 6 | Alcohols | 2.1% |
| 7 | Separation & Purification Techniques | 2.1% |
| 8 | Oxidation & Reduction | 2.0% |
| 9 | Rates of Reaction Factors | 2.0% |
| 10 | Reactivity Series | 1.9% |
Core vs Extended: the split
In our data, about 57% of questions were Extended-tier and 43% Core-tier. An A* requires the Extended papers, so weight your practice toward Extended-level questions.
Questions that come up again and again
Certain question types recur almost every series — some 9–14 times in our data. Know these cold:
- Greenhouse gases — comparing carbon dioxide and methane and their effects; one of the most repeated question types.
- Periodic table trends — statements about groups/periods, and properties of period 2 or period 4 elements.
- Identifying a gas — choosing the correct gas from a list to match a test/description.
- Physical vs chemical change — classifying a process.
- Covalent bonding — dot-and-cross diagrams for molecules like methane.
- Analysing an atmosphere — interpreting a table of gases (e.g. a "new planet").
How to turn this into a revision plan
- Front-load the big fourOrganic, Atoms/Elements/Compounds, Chemical Reactions and Metals — nearly half the paper.
- Then Acids/Bases, Stoichiometry & Periodic TableThe next high-yield band — worth solid practice.
- Drill the high-frequency topicsWriting equations, atomic structure, oxidation/reduction, rates of reaction — targeted questions on each.
- Cover the small chapters tooEnergetics and States of Matter still appear — don't leave gaps.
FAQ
What is the most tested topic in IGCSE Chemistry 0620?
Which IGCSE Chemistry topics should I revise first?
Is organic chemistry important for IGCSE 0620?
How was this data calculated?
IGCSE Chemistry rewards students who aim their revision. Lead with Organic, Atoms and Reactions, drill the high-frequency topics on real past papers, and cover the smaller chapters so nothing catches you out.
Put this into practice — free
4,168+ past papers, flashcards and an AI tutor for O Level, AS & A2. No credit card.
Start free →