Cambridge IGCSE Chemistry is a two-year course built on one repeating move: explain what you see with particles, write it as an equation, then measure it with numbers. If you can move between those three layers, a long syllabus becomes a map rather than a list.
This guide explains the code, how the course is structured, how to study it, and the order in which to work through our topic modules.
Which Chemistry syllabus am I studying?
The Cambridge IGCSE Chemistry code is 0620. Cambridge publishes each syllabus for a stated range of exam years, and the details can change between ranges.
Your school or exam centre decides your entry and route, often Core or Extended, and the code appears on your paperwork. Check the Cambridge Chemistry 0620 page for the syllabus that covers your exam year, and use the syllabus and exam-year navigator to see which of our modules apply. Our 0620 code and exam-year guide explains what to check.
We are not an exam centre. Registration, entry, results and access arrangements belong to your school or exam centre and to Cambridge.
How is the course structured?
The syllabus groups topics into areas, which include particles and structure, chemical reactions and amounts, the periodic table and reactivity, organic chemistry, and experimental techniques and analysis. The papers, durations and weightings depend on your route and exam year, so read them on the Cambridge page rather than from memory or an old resource.
Our modules follow the same logic. Each has lessons with a worked example, a mistake to avoid and a self-check, then an original practice set. Work through the assessment guide to see how to confirm which route applies to you.
How should I study Chemistry well?
Three habits change how quickly mistakes disappear.
- Work from your errors, not from the topic list. After each practice set, sort lost marks into four piles: particle idea missing, equation or formula error, calculation error, or explanation that does not fit the question. Each pile needs a different repair.
- Attach every number to a substance. Write “0.10 mol Mg” and “0.10 mol H₂”, not just “0.10”. Most wrong answers with correct arithmetic come from a ratio taken from the wrong substance.
- Say the particle reason aloud. “Rate increases because particles collide more often” is thin. “Higher concentration means more particles in the same volume, so more frequent collisions, so more successful collisions per second” is a chain.
Here is an orienting example of all three layers together. A student titrates 25.0 cm³ of 0.100 mol/dm³ sodium hydroxide with 0.125 mol/dm³ hydrochloric acid. What volume of acid is needed?
- Particles. H⁺ ions from the acid react with OH⁻ ions from the alkali, one to one.
- Equation. NaOH + HCl → NaCl + H₂O. The ratio is 1 : 1.
- Calculation. Moles NaOH = 0.0250 dm³ × 0.100 = 0.00250 mol. Moles HCl = 0.00250 mol. Volume = 0.00250 ÷ 0.125 = 0.0200 dm³, which is 20.0 cm³.
If the ratio had been 1 : 2, the same arithmetic would give 40.0 cm³ or 10.0 cm³, which is why the equation step decides the answer.
For practice, use the mole and equation-ratio tutor and the equation balance reasoning trainer. For planning, see the Chemistry study route and the revision guide.
What is the topic map, in a sensible study order?
The order below follows how topics depend on each other. Start with module 1, move down, and return to earlier modules whenever a later one exposes a gap.
Particles, atoms and bonding
- Particle models and changes of state: what particles do in solids, liquids and gases, and why.
- Atoms, elements and isotopes: the structure that explains every later pattern.
- Bonding and structure: ionic, covalent and metallic structures and the properties they explain.
Equations and amounts
- Formulas and equations: writing formulas from charges and balancing without changing them.
- Relative masses and amounts: moles, masses and the link to the equation.
- Concentration, gas and yield calculations: volumes, solutions and percentage yield.
Energy, rate and equilibrium
- Energy changes and bonds: why reactions give out or take in energy.
- Rates of reaction: collisions, conditions and how to explain a trend.
- Reversible changes and equilibrium: reactions that do not go to completion.
Reactions of acids, periodic patterns and metals
- Acids, bases and salts: neutralisation, salt preparation and titration reasoning.
- Periodic patterns: trends in groups and periods.
- Metals and reactivity: the reactivity series and what it predicts.
- Electrolysis reasoning: predicting products at each electrode, which uses ions and reactivity.
- Water, air and environmental chemistry: everyday systems that apply the earlier ideas.
Organic chemistry
- Organic families and naming: homologous series and structure.
- Organic reactions: what each family does and why.
Practical skills and communication
- Separation and chemical analysis: techniques and tests.
- Practical-data interpretation: tables, graphs and conclusions.
- Extended explanation and error repair: writing answers that fit the command word.
What are the common difficulties?
Six patterns appear again and again, and each has its own guide:
- using the wrong mole ratio despite correct arithmetic
- changing subscripts while balancing
- confusing particle size with particle spacing
- describing a rate trend without explaining it
- mixing an observation with the inferred substance
- using an old resource with unverified tier depth
The terminology guide separates terms that are often confused, such as atom, molecule and ion, or strong and concentrated. The original practice hub has explained answers.
What does individual tuition add?
A guide can show the map. It cannot watch you work. A teacher in a one-to-one lesson sees the line where your reasoning changes and asks the question that exposes it, which is hard to do from a textbook.
It helps most when mistakes repeat after honest practice, or an early gap keeps blocking new chapters. It helps less when your errors are occasional slips you can catch by checking. Practical and assessed work must stay yours, and we explain methods with original examples.
Read is one-to-one Chemistry tuition suitable for a fair comparison with self-study and group classes. The Chemistry tuition page explains the paid one-hour trial, which starts from RM80 at the assigned teacher’s confirmed rate.