Cambridge IGCSE · 0653 · Data 2020–2025
Most-tested topics in IGCSE Combined Science
Just 3 chapters — Motion, forces and energy, Electricity, Atoms, elements and compounds — carry about 29% of all the marks. Revise those first.
Based on 220 real Cambridge past papers and 28,904 tagged marks, 2020–2025. Ranked by marks, not guesswork.
Historical counts from past papers — not an exam prediction. Download the data (CSV)
Revise these first
The topics that carry the most marks, highest first. Each opens the free past-paper questions.
- 1Practise →Motion, forces and energyEvery year
- 2Practise →P4.1 Electrical quantities3% of marksElectricityEvery year
- 3Practise →P4.2 Electrical circuits3% of marksElectricityEvery year
- 4Practise →P1.5 Forces3% of marksMotion, forces and energyEvery year
- 5Practise →P1.6 Energy, work and power3% of marksMotion, forces and energyEvery year
- 6Practise →Acids, bases and saltsEvery year
- 7Practise →P1.2 Motion3% of marksMotion, forces and energyEvery year
- 8Practise →P2.2 Thermal properties and temperature2% of marksThermal physicsEvery year
See the full breakdown — all 85 topics across 33 chapters
Motion, forces and energy
16% of marks- P1.1 Physical quantities and measurement techniquesEvery year1086 marks · 130 qs
- P1.5 ForcesEvery year860 marks · 152 qs
- P1.6 Energy, work and powerEvery year858 marks · 212 qs
- P1.2 MotionEvery year784 marks · 160 qs
- P1.3 Mass and weightEvery year506 marks · 84 qs
- P1.4 DensityEvery year286 marks · 72 qs
- P1.7 PressureEvery year183 marks · 47 qs
Electricity
7% of marks- P4.1 Electrical quantitiesEvery year909 marks · 255 qs
- P4.2 Electrical circuitsEvery year882 marks · 246 qs
- P4.4 Cells, batteries, generators and motorsEvery year119 marks · 18 qs
- P4.3 Electrical safetyEvery year88 marks · 59 qs
Atoms, elements and compounds
6% of marks- C2.4 Simple molecules and covalent bondsEvery year582 marks · 124 qs
- C2.3 Ions and ionic bondsEvery year541 marks · 126 qs
- C2.2 Atomic structure and the Periodic TableEvery year441 marks · 95 qs
- C2.1 Elements, compounds and mixturesEvery year314 marks · 115 qs
Thermal physics
6% of marks- P2.2 Thermal properties and temperatureEvery year704 marks · 124 qs
- P2.3 Transfer of thermal energyEvery year659 marks · 153 qs
- P2.1 Kinetic particle model of matterEvery year314 marks · 102 qs
Waves
6% of marks- P3.3 Electromagnetic spectrumEvery year482 marks · 90 qs
- P3.2 LightEvery year473 marks · 119 qs
- P3.1 General properties of wavesEvery year363 marks · 98 qs
- P3.4 SoundEvery year288 marks · 100 qs
Organic chemistry
5% of marks- C11.4 AlkenesEvery year400 marks · 91 qs
- C11.3 AlkanesEvery year399 marks · 115 qs
- C11.1 TerminologyEvery year351 marks · 82 qs
- C11.2 FuelsEvery year339 marks · 85 qs
- C11.5 PolymersRecurring30 marks · 4 qs
Experimental techniques and chemical analysis
4% of marks- C12.4 Identification of ions and gasesEvery year633 marks · 166 qs
- C12.3 Separation and purificationEvery year319 marks · 51 qs
- C12.1 Experimental designEvery year275 marks · 31 qs
- C12.2 ChromatographyRecurring52 marks · 23 qs
Transport in animals
4% of marks- B9.2 HeartEvery year372 marks · 63 qs
- B9.4 BloodEvery year353 marks · 64 qs
- B9.3 Blood vesselsEvery year268 marks · 42 qs
- B9.1 Circulatory systemsEvery year238 marks · 30 qs
Acids, bases and salts
4% of marks- C7.1 The characteristic properties of acids and basesEvery year784 marks · 173 qs
- C7.3 Preparation of saltsEvery year359 marks · 84 qs
Chemical reactions
4% of marks- C6.2 Rate of reactionEvery year543 marks · 122 qs
- C6.3 RedoxEvery year272 marks · 100 qs
- C6.1 Physical and chemical changesEvery year239 marks · 56 qs
The Periodic Table
3% of marks- C8.4 Transition elementsEvery year229 marks · 52 qs
- C8.3 Group VII propertiesEvery year225 marks · 55 qs
- C8.2 Group I propertiesEvery year223 marks · 42 qs
- C8.5 Noble gasesRecurring170 marks · 44 qs
- C8.1 Arrangement of elementsEvery year139 marks · 47 qs
Human nutrition
3% of marks- B7.1 DietEvery year337 marks · 84 qs
- B7.3 DigestionEvery year327 marks · 111 qs
- B7.2 Digestive systemEvery year297 marks · 58 qs
Metals
3% of marks- C9.1 Properties of metalsEvery year299 marks · 81 qs
- C9.4 Reactivity seriesEvery year292 marks · 77 qs
- C9.6 Extraction of metalsEvery year187 marks · 73 qs
- C9.3 Alloys and their propertiesRecurring59 marks · 7 qs
- C9.5 Corrosion of metalsRecurring29 marks · 3 qs
Transport in plants
3% of marks- B8.3 TranspirationEvery year309 marks · 56 qs
- B8.1 Xylem and phloemEvery year266 marks · 43 qs
- B8.2 Water uptakeEvery year206 marks · 41 qs
Plant nutrition
3% of marks- B6.1 PhotosynthesisEvery year542 marks · 123 qs
- B6.2 Leaf structureEvery year197 marks · 38 qs
Organisms and their environment
2% of marks- B15.2 Food chains and food websEvery year464 marks · 103 qs
- B15.1 Energy flowEvery year142 marks · 28 qs
- B15.3 Carbon cycleEvery year107 marks · 55 qs
Chemical energetics
2% of marks- C5.1 Exothermic and endothermic reactionsEvery year675 marks · 130 qs
Reproduction
2% of marks- B14.1 Sexual reproduction in plantsEvery year317 marks · 95 qs
- B14.2 Sexual reproduction in humansEvery year294 marks · 111 qs
Enzymes
2% of marks- B5.1 EnzymesEvery year607 marks · 133 qs
Cells
2% of marks- B2.1 Cell structureEvery year333 marks · 96 qs
- B2.2 Size of specimensEvery year152 marks · 20 qs
Movement into and out of cells
2% of marks- B3.2 OsmosisEvery year245 marks · 54 qs
- B3.1 DiffusionEvery year199 marks · 51 qs
- B3.3 Active transportRecurring16 marks · 4 qs
Chemistry of the environment
2% of marks- C10.2 Air quality and climateEvery year328 marks · 81 qs
- C10.1 WaterEvery year125 marks · 41 qs
Respiration
1% of marks- B12.1 RespirationEvery year407 marks · 102 qs
Biological molecules
1% of marks- B4.1 Biological moleculesEvery year376 marks · 95 qs
Electrochemistry
1% of marks- C4.1 ElectrolysisEvery year354 marks · 105 qs
States of matter
1% of marks- C1.1 Solids, liquids and gasesEvery year334 marks · 69 qs
Characteristics of living organisms
1% of marks- B1.1 Characteristics of living organismsEvery year271 marks · 159 qs
Gas exchange in humans
1% of marks- B11.1 Gas exchange in humansEvery year209 marks · 82 qs
Diseases and immunity
1% of marks- B10.1 Diseases and immunityEvery year206 marks · 35 qs
Space physics
1% of marks- P5.1 The Solar SystemRecurring130 marks · 24 qs
- P5.2 Stars and the UniverseRecurring71 marks · 19 qs
Human influences on ecosystems
0% of marks- B16.1 Habitat destructionEvery year109 marks · 36 qs
- B16.2 ConservationOne-off33 marks · 5 qs
Stoichiometry
0% of marks- C3.1 FormulasEvery year60 marks · 28 qs
Drugs
0% of marks- B13.1 DrugsEvery year59 marks · 12 qs
Turn the data into practice
Every topic above is drawn from real Cambridge IGCSE Combined Science papers, tagged to the syllabus. Students can drill the high-frequency topics in the free bank; teachers can turn any of them into a ready-to-print worksheet in seconds. Or explore the full six-year trends in the interactive records.