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

Independent final check

Page 03

Explain without the key

calculate / determine

Final check

Supplement. Ammonia can be burned as a fuel in ships: 4NH₃ + 3O₂ → 2N₂ + 6H₂O. Breaking all the bonds in the reactants takes in 6186 kJ/mol. Making all the bonds in the products gives out 7446 kJ/mol. (a) Calculate ΔH. (b) On the reaction pathway diagram, drawn to scale, the top of the hump is 1600 kJ/mol above the products' line. Determine the activation energy, Ea.

calculate: work out the answer from the data. determine: find the answer from the information given.

Give each answer with its unit

Type numbers like 0.25 or 2.5x10^-3. Put the unit in its own box, for example g, cm3 or m/s. Leave the unit box empty if the quantity has no unit.

(a) ΔH

Number

Unit

(b) Ea

Number

Unit

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Scope and sources

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

Bond breaking and bond making (5.1 Supplement 7–8): bond breaking as endothermic and bond making as exothermic, the enthalpy change of a reaction from the energy in and the energy out, and calculating ΔH from bond energies. Exothermic and endothermic reactions, reaction pathway diagrams and activation energy are in the previous module; Hess’s law and energy cycles are not part of 0620.

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

Official Cambridge syllabus