IGCSE · Cambridge 0620

Chemistry 0620

6,186 practice questions with worked solutions, organised by topic and past-paper session. Practise any question and get your answer marked instantly.

Practise by topic

States of matter Solids, liquids and gases Diffusion Atoms, elements and compounds Elements, compounds and mixtures Atomic structure and the Periodic Table Isotopes Ions and ionic bonds Simple molecules and covalent bonds Giant covalent structures Metallic bonding Stoichiometry Formulae Relative masses of atoms and molecules The mole and the Avogadro constant Electrochemistry Electrolysis Hydrogen–oxygen fuel cells Chemical energetics Exothermic and endothermic reactions Chemical reactions Physical and chemical changes Rate of reaction Reversible reactions and equilibrium Redox Acids, bases and salts The characteristic properties of acids and bases Oxides Preparation of salts The Periodic Table Arrangement of elements Group I properties Group VII properties Transition elements Noble gases Metals Properties of metals Uses of metals Alloys and their properties Reactivity series Corrosion of metals Extraction of metals Chemistry of the environment Water Fertilisers Air quality and climate Organic chemistry Formulae, functional groups and terminology Naming organic compounds Fuels Alkanes Alkenes Alcohols Carboxylic acids Polymers Experimental techniques and chemical analysis Experimental design Acid–base titrations Chromatography Separation and purification Identification of ions and gases

By past paper

Feb/March 2017 Feb/March 2016

Example questions

Two gas jars are arranged as shown. The lid is taken off and the gas jars are left standing. After a while, the contents of both gas jars turn brown. Which process makes this happen?

Diffusion · Feb/March 2016

When concentrated hydrochloric acid undergoes electrolysis, gases P and Q are produced. Which gases are P and Q?

Electrolysis · Feb/March 2016

Which substance would not be suitable for use as a fuel when heating water in a boiler?

Fuels · Feb/March 2016

Which statement about reactions that release heat is incorrect?

Exothermic and endothermic reactions · Feb/March 2016

Which changes make the rate of reaction faster?

Rate of reaction · Feb/March 2016

Two reactions that involve water are illustrated below. X: anhydrous cobalt(II) chloride $\rightarrow$ hydrated cobalt(II) chloride Y: iron + oxygen + water $\rightarrow$ rust Which of these reactions can be reversed by heating?

Reversible reactions and equilibrium · Feb/March 2016

Iron is obtained from iron oxide using carbon monoxide, as shown below. iron oxide + carbon monoxide $\rightarrow$ iron + carbon dioxide Which statement is correct?

Extraction of metals · Feb/March 2016

Four separate solutions, W, X, Y and Z, are checked with Universal Indicator. Solution W produces green, X produces red, Y produces purple, and Z produces orange. Which solutions are acidic?

The characteristic properties of acids and bases · Feb/March 2016

Methyl orange becomes red in the solution produced when substance R reacts with water. Which substance is R?

The characteristic properties of acids and bases · Feb/March 2016

A salt is prepared by reacting an excess of an insoluble metal oxide with an acid. How is the extra metal oxide separated from the mixture?

Preparation of salts · Feb/March 2016