IGCSE Chemistry 0620 Paper 11, Oct/Nov 2025

Which process describes the movement of a substance very slowly from an area of high concentration to an area of low concentration? A a liquid being frozen B a solid melting C a substance diffusing through a liquid D a substance diffusing through the air

The atomic number and nucleon number of a potassium atom are shown.

How many protons, neutrons and electrons are in the potassium ion, ${\text{K}}^{+}$, which is formed from this potassium atom?

Magnesium is in Group II and Period 3 of the Periodic Table. Which row shows the charge on a magnesium ion and the electronic configuration of a magnesium ion?

Sodium is in Group I of the Periodic Table. Chlorine is in Group VII of the Periodic Table. Sodium and chlorine combine to form a compound. Which statement about the combination of sodium and chlorine atoms is correct? A Both sodium and chlorine lose electrons. B Both sodium and chlorine gain electrons. C Sodium loses electrons and chlorine gains electrons. D Sodium gains electrons and chlorine loses electrons.

Strontium nitrate is an ionic compound. Cyclohexane is a covalent compound. Which row describes a property of each compound?

Which element forms covalent bonds with hydrogen? A magnesium B neon C nitrogen D sodium

Which statement about graphite and diamond is correct? A Diamond has a high melting point but graphite does not. B Graphite and diamond both conduct electricity. C Graphite and diamond both have giant structures. D Graphite is ionic and diamond is covalent.

Carbon dioxide gas reacts with aqueous calcium hydroxide to form calcium carbonate. Which equation represents this reaction? A ${\text{CO}}_2(\text{g})+{\text{Ca(OH)}}_2(\text{aq})\to {\text{CaCO}}_3(\text{s})+{\text{H}}_2\text{O}(\text{l})$ B ${\text{CO}}_2(\text{g})+{\text{Ca(OH)}}_2(\text{aq})\to {\text{CaCO}}_3(\text{aq})+{\text{H}}_2\text{O}(\text{l})$ C $2{\text{CO}}_2(\text{g})+2\text{CaOH}(\text{aq})\to 2{\text{CaCO}}_3(\text{s})+{\text{H}}_2(\text{g})$ D $2{\text{CO}}_2(\text{g})+2\text{CaOH}(\text{aq})\to 2{\text{CaCO}}_3(\text{aq})+{\text{H}}_2(\text{g})$

The equation for the combustion of magnesium is shown. $$2\text{Mg}+{\text{O}}_2\to 2\text{MgO}$$ Which mass of magnesium oxide will be formed from the complete reaction of $9.6\text{g}$ of magnesium? A $8.0\text{g}$ B $16.0\text{g}$ C $24.0\text{g}$ D $40.0\text{g}$

Which row identifies the product at each electrode when molten zinc chloride is electrolysed using inert electrodes?

Which equation represents the reaction in a hydrogen–oxygen fuel cell? A $2{\text{H}}_2+{\text{O}}_2\to 2{\text{H}}_2\text{O}$ B $2{\text{H}}_2+2\text{O}\to 2{\text{H}}_2\text{O}$ C $2{\text{H}}_2\text{O}\to 2{\text{H}}_2+{\text{O}}_2$ D $2{\text{H}}_2\text{O}\to 2{\text{H}}_2+2\text{O}$

What is always produced when a fuel is burned? A carbon dioxide B carbon monoxide C oxides of nitrogen D thermal energy

The reaction pathway diagram shows the energy of the reactants and products in a chemical reaction. Which row describes the enthalpy change and the type of reaction shown?

Magnesium is reacted with dilute hydrochloric acid of the same concentration in four experiments using different conditions. Which reaction finished in the shortest time? A $2\text{g}$ of magnesium powder in $50{\text{cm}}^3$ of dilute $\text{HCl}$ at $45{}^{\circ }\text{C}$ B $2\text{g}$ of magnesium powder in $50{\text{cm}}^3$ of dilute $\text{HCl}$ at $50{}^{\circ }\text{C}$ C $2\text{g}$ of magnesium ribbon in $50{\text{cm}}^3$ of dilute $\text{HCl}$ at $45{}^{\circ }\text{C}$ D $2\text{g}$ of magnesium ribbon in $50{\text{cm}}^3$ of dilute $\text{HCl}$ at $50{}^{\circ }\text{C}$

Blue hydrated copper(II) sulfate produces a white solid when it is heated. The white solid turns blue when water is added. Which word describes the reaction of hydrated copper(II) sulfate? A neutralisation B oxidation C reduction D reversible

Iron(III) chloride, ${\text{FeCl}}_3$, is a brown solid. What is the meaning of (III) in the name? A It is the amount of energy released when the compound was formed. B It is the rate of the reaction that formed this compound. C It is how many atoms of iron are bonded together in the compound. D It is the oxidation number of iron in the compound.

What are the units of concentration? A $\text{mol}\mathrm{/}{\text{dm}}^3$ B $\text{g}\mathrm{/}\text{dm}$ C ${\text{dm}}^3\mathrm{/}\text{mol}$ D $\text{cm}\mathrm{/}\text{g}$

Which pair of reactants are both soluble in water and mix to form a precipitate? A $\text{NaCl}$ and ${\text{Mg(NO}}_3{)}_2$ B ${\text{BaSO}}_4$ and ${\text{K}}_2{\text{CO}}_3$ C ${\text{CaCl}}_2$ and ${\text{NaNO}}_3$ D ${\text{Pb(NO}}_3{)}_2$ and $\text{KCl}$

Four oxides are listed. 1 lithium oxide 2 phosphorus oxide 3 sodium oxide 4 sulfur dioxide Which oxides are basic? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

Cobalt is a typical transition element. Which statement about cobalt is correct? A Cobalt has a low density. B Cobalt has a low melting point. C Cobalt can form only colourless compounds. D Cobalt can act as a catalyst.

Which diagrams show the electronic configuration for an atom of a noble gas? A 1 and 2 B 1 and 3 C 2 only D 3 only

Which statement describes the alloy brass? A It is a mixture of iron and nickel. B It is a mixture of iron compounds. C It is a compound of copper, zinc and non-metals. D It is a mixture of the metals copper and zinc.

The results of the reaction of metals W, X, Y and Z with cold water and dilute acid are shown.

What is the order of reactivity of the metals?

Some methods of preventing iron from rusting are listed. 1 alloying with chromium 2 greasing 3 painting Which methods are barrier methods? A 1 and 2 B 1 and 3 C 2 and 3 D 3 only

Which metal is extracted from bauxite by electrolysis? A aluminium B copper C iron D zinc

Which statement about water is correct? A When water is added to solid anhydrous cobalt(II) chloride, the solid turns blue. B Water containing dissolved sodium chloride boils at a temperature greater than $100{}^{\circ }\text{C}$. C All dissolved metal ions found in natural sources of water are beneficial to life. D Soluble impurities are removed during the sedimentation stage in the treatment of drinking water.

What is the structure of ethanol?

Which statement about alkanes is correct? A They contain carbon, hydrogen and oxygen only. B They are saturated compounds with only single ionic bonds. C The alkanes with longer chain lengths are more volatile. D They react with chlorine in a substitution reaction.

Which row identifies an adverse effect of the named pollutant?

Which group of compounds have the same general formula? A ${\text{CH}}_4$, ${\text{C}}_2{\text{H}}_6$, ${\text{C}}_3{\text{H}}_6$ B ${\text{CH}}_4$, ${\text{C}}_3{\text{H}}_6$, ${\text{C}}_4{\text{H}}_8$ C ${\text{C}}_2{\text{H}}_4$, ${\text{C}}_3{\text{H}}_6$, ${\text{C}}_4{\text{H}}_8$ D ${\text{C}}_2{\text{H}}_4$, ${\text{C}}_3{\text{H}}_8$, ${\text{C}}_4{\text{H}}_8$

Some fractions obtained from petroleum are listed.

Which rows are correct? A 1, 3 and 4 B 2, 3 and 4 C 3 and 4 only D 4 only

Four different substances or types of substance are listed. 1 hydrogen 2 alcohols 3 alkenes 4 carboxylic acids Which substances are produced by cracking larger alkane molecules? A 1 and 3 B 1 only C 2, 3 and 4 D 2 and 4 only

Which row shows the conditions used to manufacture ethanol from ethene and steam?

Which statement about aqueous ethanoic acid is correct? A It reacts with metal carbonates to form salts, hydrogen and water. B It reacts with metal oxides to form salts and oxygen. C It reacts with reactive metals to form salts and hydrogen. D It turns damp red litmus paper blue.

The equation represents a polymerisation reaction. $$n{\text{CH}}_2={\text{CH}}_2\to \text{—}[\text{—}{\text{CH}}_2-{\text{CH}}_2\text{—}{]}_n\text{—}$$ Which statements are correct? 1 The monomer is ethane. 2 The reaction is addition polymerisation. 3 The polymer does not easily decompose. A 1 and 3 B 1 only C 2 and 3 D 2 only

A sample of wax is heated. It begins to melt at $45{}^{\circ }\text{C}$ and finishes melting at $49{}^{\circ }\text{C}$. A sample of liquid is heated. It begins to boil at $141{}^{\circ }\text{C}$ and remains at $141{}^{\circ }\text{C}$ while it boils. Which conclusion can be made from these results? A Both substances are impure. B Both substances are pure. C The wax is not a pure substance and the liquid is a pure substance. D The wax is a pure substance and the liquid is not a pure substance.

Four dyes, P, Q, R and S, are analysed using chromatography. Water is the solvent. The chromatogram produced is shown. Which statement about the dyes is correct? A All four dyes are impure. B The four dyes contain a total of eight different substances. C Dye R is a mixture of dye P and dye Q. D Dye S is a mixture of dye Q and one other substance.

The apparatus used to separate a mixture is shown. What is the mixture? A aqueous calcium chloride and aqueous calcium nitrate B copper(II) hydroxide and aqueous calcium chloride C ethanol and water D sand and calcium carbonate

Two different white solids are heated and the gases formed are tested. The gas from solid 1 turns damp red litmus paper blue. The gas from solid 2 relights a glowing splint. Which row identifies the gases formed from each solid?

Which aqueous ion gives a blue precipitate when aqueous sodium hydroxide is added? A ${\text{Ca}}^{2+}$ B ${\text{Cr}}^{3+}$ C ${\text{Cu}}^{2+}$ D ${\text{Fe}}^{2+}$