Contents

States of matter

Atoms, elements and compounds

Stoichiometry

Electrochemistry

ElectrolysisBeing prepared
Electrolysis of solutions and electroplatingBeing prepared
Fuel cellsBeing prepared

Chemical energetics

Chemical reactions

Acids, bases and salts

Acids, bases and indicators
OxidesBeing prepared
Making saltsBeing prepared

The Periodic Table

Reading the tableBeing prepared
Group I: the alkali metalsBeing prepared
Group VII: the halogensBeing prepared
Transition elements and noble gasesBeing prepared

Metals

Metals and alloysBeing prepared
The reactivity seriesBeing prepared
CorrosionBeing prepared
Extracting metalsBeing prepared

Chemistry of the environment

WaterBeing prepared
FertilisersBeing prepared
Air quality and climateBeing prepared

Organic chemistry

Naming organic moleculesBeing prepared
Crude oil and alkanesBeing prepared
AlkenesBeing prepared
Alcohols and carboxylic acidsBeing prepared
PolymersBeing prepared

Experimental techniques and chemical analysis

Mixtures and separation
Measuring and planning experimentsBeing prepared
Crystallisation
Distillation
Paper chromatography
Choosing methods and checking purityBeing prepared
TitrationBeing prepared
Gas testsBeing prepared
Anion testsBeing prepared
Cation and flame testsBeing prepared

Part 1 of 2

Page 01

How heavy is a water molecule?

describe

Try it yourself

Which statement describes the relative atomic mass, A_r, of an element?

describe: give the features or what happens.

Choose one answera.The average mass of its isotopes, compared to 1/12 of the mass of a carbon-12 atomb.The total number of protons and neutrons in one atom of the elementc.The mass of its most common isotope, compared to 1/12 of the mass of a carbon-12 atomd.The actual mass of one atom of the element, measured in grams

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Scope and sources

Cambridge IGCSE Chemistry 0620 · 2026–2028 v2 · Original learning materials.

Relative masses (3.2 Core 1–3): relative atomic mass as the average mass of the isotopes of an element compared to 1/12 of the mass of an atom of carbon-12, relative molecular mass and relative formula mass as the sum of the relative atomic masses, and reacting masses in simple proportions, without the mole. The mole and molar mass, calculating relative atomic mass from isotope abundances, percentage yield and purity are left to other modules.

Apparatus, amounts and times in the experiment are illustrative. Real practical work follows a teacher-approved safety method.

Official Cambridge syllabus