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 3

Page 01

The gas syringe race

determine / describe

Try it yourself

Iron filings react with dilute hydrochloric acid in a flask, and the hydrogen is collected in a gas syringe. The table shows the volume of gas in the syringe. (a) Determine the volume of hydrogen collected in the first 30 s. (b) Determine the volume collected between 30 s and 60 s. (c) Describe what your answers show about the rate of the reaction.

determine: find the answer from the information given. describe: give the features or what happens.

Time / s	0	30	60	90	120	150	180
Volume of hydrogen / cm³	0	33	54	66	72	74	74

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) Hydrogen in the first 30 s

Number

Unit

(b) Hydrogen from 30 s to 60 s

Number

Unit

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Scope and sources

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

Rate of reaction (6.2 Core 1–4, Supplement 5–8): the effect of concentration, gas pressure, surface area, temperature and a catalyst, catalysts and enzymes, practical methods for following a rate and interpreting its data, collision theory and activation energy. Moles and gas volumes are in an earlier module; reversible reactions and equilibrium in 6.3.

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

Official Cambridge syllabus