IGCSE Chemistry High-Yield Theory Questions
Questions that appear every year with exact mark scheme answers. Based on analysis of 525+ theory questions across 37+ papers.
All 37 Topics by Exam Weight
Sorted from most marks to least. Red = high priority, Orange = medium, Gray = lower priority.
Marks by Year & Session
Format: Total (Mar/May/Nov)
| Topic | Total | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|
| Solids, liquids and gases | 687 | 177 16/83/78 | 182 0/104/78 | 169 27/88/54 | 159 14/78/67 |
| Acids and bases | 607 | 128 8/93/27 | 148 0/58/90 | 136 33/39/64 | 195 22/83/90 |
| Reactivity series | 501 | 100 17/20/63 | 136 10/61/65 | 170 21/103/46 | 95 0/49/46 |
| Electrolysis | 440 | 78 23/28/27 | 172 11/111/50 | 104 12/42/50 | 86 16/54/16 |
| Calculations | 438 | 113 0/58/55 | 73 36/28/9 | 114 16/0/98 | 138 17/46/75 |
| Formulae | 381 | 70 17/19/34 | 74 17/29/28 | 100 25/61/14 | 137 34/13/90 |
| Group I - Alkali metals | 377 | 172 41/47/84 | 68 26/9/33 | 57 0/46/11 | 80 0/29/51 |
| Particle theory | 289 | 87 11/0/76 | 16 0/0/16 | 104 0/64/40 | 82 0/49/33 |
| Elements, compounds and mixtures | 244 | 67 8/42/17 | 50 6/18/26 | 89 15/44/30 | 38 14/24/0 |
| Reversible reactions and equilibrium | 237 | 30 0/0/30 | 83 18/32/33 | 40 0/20/20 | 84 14/53/17 |
| Air and air quality | 206 | 54 15/25/14 | 59 16/13/30 | 57 14/43/0 | 36 7/29/0 |
| Experimental design | 151 | 43 18/0/25 | 81 0/39/42 | 15 0/0/15 | 12 0/0/12 |
| Group VII - Halogens | 145 | 31 0/11/20 | 44 0/44/0 | 58 18/7/33 | 12 0/12/0 |
| Hydrogen-oxygen fuel cells | 134 | 17 7/10/0 | 44 11/6/27 | 50 14/8/28 | 23 0/0/23 |
| Gases and the gas laws | 133 | 86 26/53/7 | 9 0/0/9 | 38 0/38/0 | 0 0/0/0 |
| Formulae, functional groups and nomenclature | 131 | 33 9/15/9 | 30 0/13/17 | 25 0/12/13 | 43 0/14/29 |
| Transition elements | 122 | 42 0/42/0 | 50 18/0/32 | 0 0/0/0 | 30 0/30/0 |
| Atomic structure | 112 | 34 0/26/8 | 17 0/17/0 | 14 0/0/14 | 47 6/19/22 |
| Alcohols | 102 | 29 0/20/9 | 40 13/27/0 | 26 0/13/13 | 7 0/7/0 |
| Oxides | 87 | 17 0/9/8 | 12 0/12/0 | 0 0/0/0 | 58 0/47/11 |
| Identification of ions and gases | 83 | 19 0/10/9 | 35 25/10/0 | 9 0/9/0 | 20 9/0/11 |
| Rate of reaction | 79 | 0 0/0/0 | 21 7/14/0 | 19 0/0/19 | 39 39/0/0 |
| Arrangement of elements | 73 | 38 0/38/0 | 18 0/10/8 | 0 0/0/0 | 17 13/0/4 |
| Corrosion | 71 | 0 0/0/0 | 41 14/10/17 | 0 0/0/0 | 30 11/0/19 |
| Polymers | 51 | 18 0/9/9 | 19 0/19/0 | 14 0/0/14 | 0 0/0/0 |
| Water | 45 | 0 0/0/0 | 6 0/0/6 | 22 0/0/22 | 17 0/7/10 |
| Esters | 44 | 18 0/18/0 | 12 0/0/12 | 14 0/14/0 | 0 0/0/0 |
| Uses of metals | 44 | 15 0/0/15 | 9 0/0/9 | 0 0/0/0 | 20 0/7/13 |
| Carboxylic acids | 42 | 24 0/0/24 | 0 0/0/0 | 0 0/0/0 | 18 0/18/0 |
| Bonding | 37 | 8 0/0/8 | 0 0/0/0 | 24 0/0/24 | 5 0/0/5 |
Topic Questions & Answers
Click each topic to see common question types and mark scheme guidance.
Common question types and mark scheme points for Solids, liquids and gases:
• Define/describe key concepts related to Solids, liquids and gases
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Acids and bases:
• Define/describe key concepts related to Acids and bases
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Reactivity series:
• Define/describe key concepts related to Reactivity series
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Electrolysis:
• Define/describe key concepts related to Electrolysis
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Calculations:
• Define/describe key concepts related to Calculations
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Formulae:
• Define/describe key concepts related to Formulae
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Group I - Alkali metals:
• Define/describe key concepts related to Group I - Alkali metals
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Particle theory:
• Define/describe key concepts related to Particle theory
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Elements, compounds and mixtures:
• Define/describe key concepts related to Elements, compounds and mixtures
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Reversible reactions and equilibrium:
• Define/describe key concepts related to Reversible reactions and equilibrium
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Air and air quality:
• Define/describe key concepts related to Air and air quality
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Experimental design:
• Define/describe key concepts related to Experimental design
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Group VII - Halogens:
• Define/describe key concepts related to Group VII - Halogens
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Hydrogen-oxygen fuel cells:
• Define/describe key concepts related to Hydrogen-oxygen fuel cells
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Gases and the gas laws:
• Define/describe key concepts related to Gases and the gas laws
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Formulae, functional groups and nomenclature:
• Define/describe key concepts related to Formulae, functional groups and nomenclature
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Transition elements:
• Define/describe key concepts related to Transition elements
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Atomic structure:
• Define/describe key concepts related to Atomic structure
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Alcohols:
• Define/describe key concepts related to Alcohols
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Oxides:
• Define/describe key concepts related to Oxides
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Identification of ions and gases:
• Define/describe key concepts related to Identification of ions and gases
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Rate of reaction:
• Define/describe key concepts related to Rate of reaction
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Arrangement of elements:
• Define/describe key concepts related to Arrangement of elements
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Corrosion:
• Define/describe key concepts related to Corrosion
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Polymers:
• Define/describe key concepts related to Polymers
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Water:
• Define/describe key concepts related to Water
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Esters:
• Define/describe key concepts related to Esters
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Uses of metals:
• Define/describe key concepts related to Uses of metals
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Carboxylic acids:
• Define/describe key concepts related to Carboxylic acids
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Common question types and mark scheme points for Bonding:
• Define/describe key concepts related to Bonding
• Explain processes and mechanisms
• Compare and contrast with related topics
• Apply knowledge to unfamiliar contexts
Sample questions to be added from past papers
Generated on 2026-02-23 | Data from Cambridge IGCSE Chemistry 0620 papers
Last updated