Ions and ionic bonds — Paper 2 · IGCSE Science - Combined 0653

15 Magnesium reacts with sulfur, to form magnesium sulfide. Magnesium sulfide is an ionic compound. Which statement is not correct? A Electrons are shared between sulfur and magnesium. B Electrons are transferred from magnesium to sulfur. C The magnesium ions are positively charged. D The sulfur atoms gain electrons.

1 marks

Answer: A

This question in 0653/22 Feb/March 2017

22 Which statements about elements in the Periodic Table are correct? 1 The higher the group number, the more metallic an element is. 2 The group number is equal to the number of electrons in the outer shell. 3 Elements on the left of the Periodic Table form ions by losing electrons. A 1 only B 1 and 2 C 1 and 3 D 2 and 3

1 marks

Answer: D

This question in 0653/22 Feb/March 2017

17 Aluminium ions have the formula Al 3+. Oxide ions have the formula O2–. What is the formula of aluminium oxide? A Al O B Al O2 C Al 2O3 D Al 3O2

1 marks

Answer: C

This question in 0653/21 May/June 2017

16 Which row describes the electronic structures of a chlorine atom and of a sodium ion? chlorine atom sodium ion A 2,8,7 2,8 B 2,8,7 2,8,8 C 2,8,8 2,8 D 2,8,8 2,8,8

1 marks

Answer: A

This question in 0653/22 May/June 2017

17 Aluminium ions have the formula Al 3+. Oxide ions have the formula O2–. What is the formula of aluminium oxide? A Al O B Al O2 C Al 2O3 D Al 3O2

1 marks

Answer: C

This question in 0653/22 May/June 2017

15 Which elements react together to give positive ions and negative ions that have the same electronic structure as argon? A calcium and chlorine B calcium and fluorine C magnesium and chlorine D magnesium and fluorine

1 marks

Answer: A

This question in 0653/23 May/June 2017

16 What is the electronic structure of a chlorine atom, Cl, and of a chloride ion, Cl –? chlorine atom chloride ion A 2,8,6 2,8,8 B 2,8,7 2,8,6 C 2,8,7 2,8,8 D 2,8,8 2,8,7

1 marks

Answer: C

This question in 0653/21 Oct/Nov 2017

18 Aluminium sulfate contains aluminium ions, Al 3+, and sulfate ions, SO4 2–. Iron(II) nitride contains iron(II) ions, Fe2+, and nitride ions, N3–. What are the formulae of aluminium sulfate and of iron(II) nitride? aluminium sulfate iron(II) nitride A Al 2(SO4)3 Fe2N3 B Al 2(SO4)3 Fe3N2 C Al 3(SO4)2 Fe2N3 D Al 3(SO4)2 Fe3N2

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2017

17 The electronic structure of a sodium atom is 2,8,1. The electronic structure of a sodium ion is 2,8. Which statement is not correct? A Sodium ions form metallic bonds. B The electronic structure of a sodium ion is more stable than that of a sodium atom. C The sodium atom loses one electron to become an ion. D The sodium ion has a noble gas electronic structure.

1 marks

Answer: A

This question in 0653/22 Oct/Nov 2017

16 Which statement describes how sodium atoms and oxygen atoms combine to form sodium oxide, Na2O? A One sodium atom gains two electrons and two oxygen atoms lose one electron each. B One sodium atom loses two electrons and two oxygen atoms gain one electron each. C Two sodium atoms gain one electron each and one oxygen atom loses two electrons. D Two sodium atoms lose one electron each and one oxygen atom gains two electrons.

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2017

18 The formulae of some ions are shown. ● ammonium, NH4 + ● calcium, Ca2+ ● nitrate, NO3 – ● phosphate, PO4 3– What is the formula of calcium nitrate and of ammonium phosphate? calcium nitrate ammonium phosphate A Ca(NO3)2 NH4(PO4)3 B Ca(NO3)2 (NH4)3PO4 C Ca2NO3 NH4(PO4)3 D Ca2NO3 (NH4)3PO4

1 marks

Answer: B

This question in 0653/23 Oct/Nov 2017

19 Which row describes an ionic compound? can be melting point electrolysed A high no B high yes C low no D low yes

1 marks

Answer: B

This question in 0653/23 Oct/Nov 2017

16 Which statement about atoms and ions is not correct? A A chlorine atom loses one electron to obtain a noble gas electronic structure. B A magnesium atom has two valency electrons. C A sodium ion, Na+, has eight electrons in its outer shell. D Oxygen atoms and oxide ions each have two occupied electron shells.

1 marks

Answer: A

This question in 0653/22 Feb/March 2018

17 The formula of a sodium ion is Na+. The formula of an oxide ion is O2–. What is the formula of sodium oxide? A NaO B NaO2 C Na2O D Na2O3

1 marks

Answer: C

This question in 0653/21 May/June 2018

17 An ion of element X has 8 protons, 8 neutrons and 10 electrons. An ion of element Y has 11 protons, 12 neutrons and 10 electrons. What is the formula of the ionic compound formed between X and Y? A XY B XY2 C X2Y D X2Y2

1 marks

Answer: B

This question in 0653/22 May/June 2018

24 Part of the Periodic Table is shown. I II III IV V VI VII VIII V W X Which element forms an anion and which element forms a cation? forms an anion forms a cation A V W B V X C W V D X W

1 marks

Answer: C

This question in 0653/22 May/June 2018

17 Chromium oxide contains chromium ions, Cr3+, and oxide ions, O2–. What is the formula of chromium oxide? A CrO B CrO2 C Cr2O3 D Cr3O2

1 marks

Answer: C

This question in 0653/23 May/June 2018

18 During the electrolysis of molten potassium chloride, which particles in the electrolyte move towards the cathode? A electrons B chloride ions C chlorine molecules D potassium ions

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2018

16 Which statement about the compound formed between a metal and a non-metal is correct? A It forms strong bonds by sharing electrons. B It has strong bonds between its atoms. C It has strong bonds between metal ions and delocalised electrons. D It has strong bonds between oppositely charged ions.

1 marks

Answer: D

This question in 0653/22 Feb/March 2019

16 Magnesium chloride is an ionic compound. Which row describes the formation of magnesium chloride and the strength of the attraction between its ions? strength of the formation of magnesium chloride attraction between ions A electrons are shared between magnesium and chlorine strong B electrons are shared between magnesium and chlorine weak C electrons are transferred from magnesium to chlorine strong D electrons are transferred from magnesium to chlorine weak

1 marks

Answer: C

This question in 0653/21 May/June 2019

17 Which statement about sodium ions and chloride ions in sodium chloride is not correct? A They are strongly attracted to each other. B They both have noble gas electronic structures. C They are arranged in a regular lattice. D They share pairs of electrons.

1 marks

Answer: D

This question in 0653/22 May/June 2019

16 Which statement explains why sodium chloride has a much higher melting point than carbon dioxide? A Ionic bonding is weaker than covalent bonding. B Ionic bonding is stronger than covalent bonding. C The attractive forces between ions are stronger than the attractive forces between molecules. D The attractive forces between ions are weaker than the attractive forces between molecules.

1 marks

Answer: C

This question in 0653/23 May/June 2019

17 Some information about a sodium ion is shown. proton nucleon number of number of number of particle number number protons neutrons electrons Na+ 11 23 11 X Y What are the values of X and Y? X Y A 11 10 B 11 11 C 12 10 D 12 11

1 marks

Answer: C

This question in 0653/22 Feb/March 2020

26 Which statement describes the structure of sodium chloride? A It is composed of a regular arrangement of alternating positive and negative ions. B It is composed of negatively charged sodium ions joined to positively charged chloride ions. C It is composed of oppositely charged ions held together by strong covalent bonds. D It is composed of sodium atoms joined to chlorine atoms by shared pairs of electrons.

1 marks

Answer: A

This question in 0653/22 Feb/March 2020

16 Which ion is formed from a metal? A Cl – B H+ C Na+ D NH4 +

1 marks

Answer: C

This question in 0653/21 May/June 2020

16 A magnesium ion, Mg2+, is formed from a magnesium atom, Mg. Which row about the numbers of protons and neutrons in the magnesium ion and in the magnesium atom is correct? number of protons number of neutrons A larger in Mg2+ than in Mg same in Mg and Mg2+ B same in Mg and Mg2+ same in Mg and Mg2+ C same in Mg and Mg2+ smaller in Mg2+ than in Mg D smaller in Mg2+ than in Mg larger in Mg2+ than in Mg

1 marks

Answer: B

This question in 0653/22 May/June 2020

16 Which statement about the formation of ions is correct? A Metal atoms gain electrons to form cations and non-metal atoms lose electrons to form anions. B Metal atoms gain electrons to form anions and non-metal atoms lose electrons to form cations. C Metal atoms lose electrons to form cations and non-metal atoms gain electrons to form anions. D Metal atoms lose electrons to form anions and non-metal atoms gain electrons to form cations.

1 marks

Answer: C

This question in 0653/22 Oct/Nov 2020

17 The formula of a magnesium ion is Mg2+. The formula of a nitride ion is N3–. What is the formula of magnesium nitride? A MgN B Mg2N2 C Mg2N3 D Mg3N2

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2020

16 Potassium chloride is a solid. Hydrogen chloride is a gas. Which statement explains why potassium chloride has a much higher boiling point than hydrogen chloride? A Covalent bonding is stronger than ionic bonding. B Covalent bonds are stronger than the attractive forces between molecules. C Ionic bonding is stronger than covalent bonding. D Ionic bonds are stronger than the attractive forces between molecules.

1 marks

Answer: D

This question in 0653/22 Feb/March 2021

17 Ammonium phosphate has the formula (NH4)3PO4. Which row shows the formulae of ammonium ions and phosphate ions? ammonium phosphate A NH4 + PO4 – B NH4 3+ PO4 3– C NH4 + PO4 3– D NH4 3+ PO4 –

1 marks

Answer: C

This question in 0653/22 Feb/March 2021

17 The symbols and charges of some ions are shown. ● aluminium, Al 3+ ● phosphate, PO4 3– ● sodium, Na+ ● sulfate, SO4 2– What are the formulae of aluminium sulfate and sodium phosphate? aluminium sodium sulfate phosphate A Al 2(SO4)3 Na3PO4 B Al 2(SO4)3 Na(PO4)3 C Al 3(SO4)2 Na3PO4 D Al 3(SO4)2 Na(PO4)3

1 marks

Answer: A

This question in 0653/21 May/June 2021

15 Which statement explains why ionic compounds have higher melting points than covalent compounds? A Attractive forces are stronger between ions than between molecules. B Ionic bonds are stronger than covalent bonds. C Ions are formed by the transfer of electrons from one atom to another. D The atoms in covalent molecules share electrons.

1 marks

Answer: A

This question in 0653/21 Oct/Nov 2021

15 The formula of magnesium chloride is MgCl 2. The formula of sodium phosphide is Na3P. What is the formula of magnesium phosphide? A MgP B MgP2 C Mg2P3 D Mg3P2

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2021

15 Which statement explains the difference in boiling point between ionic and covalent compounds? A The boiling point of covalent compounds is higher because covalent bonds are stronger than ionic bonds. B The boiling point of covalent compounds is higher because the attractive forces between covalent molecules are stronger than the attractive forces between ions. C The boiling point of ionic compounds is higher because the attractive forces between ions are stronger than covalent bonds. D The boiling point of ionic compounds is higher because the attractive forces between ions are stronger than the attractive forces between covalent molecules.

1 marks

Answer: D

This question in 0653/21 Oct/Nov 2022

15 Which row describes and explains the difference in melting points between ionic and covalent compounds? melting point reason A ionic compounds have ionic bonds are stronger higher melting points than covalent bonds B ionic compounds have attractive forces between ions are stronger higher melting points than attractive forces between molecules C ionic compounds have ionic bonds are weaker lower melting points than covalent bonds D ionic compounds have attractive forces between ions are weaker lower melting points than attractive forces between molecules

1 marks

Answer: B

This question in 0653/22 Oct/Nov 2022

16 Potassium phosphate is an ionic compound used in fertilisers. Phosphate ions have the symbol PO4 3–. What is the formula for potassium phosphate? A KPO4 B K(PO4)3 C K2PO4 D K3PO4

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2022

15 Which elements react together to give positive ions and negative ions that all have the same electronic structure as argon? A calcium and chlorine B calcium and fluorine C magnesium and chlorine D magnesium and fluorine

1 marks

Answer: A

This question in 0653/22 Feb/March 2023

16 Sodium reacts with chlorine to form sodium chloride. Which statement describes a change that occurs during this reaction? A Each chlorine atom loses one proton. B Each sodium atom loses one electron. C The mass number of each chlorine atom increases. D The atomic number of sodium decreases.

1 marks

Answer: B

This question in 0653/21 May/June 2023

16 Which structure represents an ionic compound? A B C D + – H H H Li F H C C C H Cl Cl H H H

1 marks

Answer: A

This question in 0653/22 May/June 2023

16 Which dot-and-cross diagram represents lithium fluoride, LiF? A B + – Li F Li F C D + – Li F Li F

1 marks

Answer: B

This question in 0653/23 May/June 2023

17 Iron(III) sulfate contains Fe3+ ions and SO4 2– ions. What is the formula of iron(III) sulfate? A FeSO4 B Fe3SO4 C Fe2(SO4)3 D Fe3(SO4)2

1 marks

Answer: C

This question in 0653/21 Oct/Nov 2023

16 Which statement about the boiling points of covalent compounds such as CO2 and ionic compounds is correct? A These covalent compounds have higher boiling points than ionic compounds because covalent bonds are stronger than ionic bonds. B These covalent compounds have higher boiling points than ionic compounds because the attractive forces between covalent molecules are stronger than the attractive forces between ions. C Ionic compounds have higher boiling points than these covalent compounds because ionic bonds are stronger than covalent bonds. D Ionic compounds have higher boiling points than these covalent compounds because the attractive forces between ions are stronger than the attractive forces between covalent molecules.

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2023

17 An ionic compound contains ammonium ions, NH4 +, iron(III) ions, Fe3+, and sulfate ions, SO4 2–. What is the formula of this compound? A NH4FeSO4 B NH4Fe(SO4)2 C (NH4)2FeSO4 D NH4Fe3(SO4)2

1 marks

Answer: B

This question in 0653/22 Oct/Nov 2023

16 Which statement about the melting points of aluminium oxide, Al 2O3, and methanol, CH3OH, is correct? A Aluminium oxide has a higher melting point than methanol because ionic bonding is stronger than covalent bonding. B Aluminium oxide has a higher melting point than methanol because the attraction between ions is stronger than the attraction between molecules. C Methanol has a higher melting point than aluminium oxide because covalent bonding is stronger than ionic bonding. D Methanol has a higher melting point than aluminium oxide because the attraction between molecules is stronger than the attraction between ions.

1 marks

Answer: B

This question in 0653/23 Oct/Nov 2023

16 Which statement about the structure of solid sodium chloride is correct? A It contains chloride ions formed when chlorine atoms lose electrons. B It contains metallic atoms sharing electrons with non-metallic atoms. C Opposite electrical charges result in the formation of a giant ionic lattice. D There is strong electrostatic attraction between sodium atoms and chlorine atoms.

1 marks

Answer: C

This question in 0653/22 Feb/March 2024

17 An ionic compound contains the ions NH4 + and S2O3 2–. What is the formula of this compound? A NH4S2O3 B NH4(S2O3)2 C (NH4)2S2O3 D 2NH4S2O3

1 marks

Answer: C

This question in 0653/22 Feb/March 2024

17 The formula of magnesium nitrate is Mg(NO3)2. Which symbols represent the ions in magnesium nitrate? magnesium nitrate A Mg+ NO3 – B Mg+ NO3 2– C Mg2+ NO3 2– D Mg2+ NO3 –

1 marks

Answer: D

This question in 0653/21 May/June 2024

16 Which statement describes the formation of ions when two different atoms combine? A The two atoms share a pair of electrons. B Both atoms lose electrons. C Both atoms gain electrons. D One atom gains electrons and one loses electrons.

1 marks

Answer: D

This question in 0653/22 May/June 2024

16 Magnesium chloride is an ionic compound. Which row describes the formation of magnesium chloride and the strength of the attraction between its ions? strength of the formation of magnesium chloride attraction between ions A Electrons are shared between magnesium and chlorine. strong B Electrons are shared between magnesium and chlorine. weak C Electrons are transferred from magnesium to chlorine. strong D Electrons are transferred from magnesium to chlorine. weak

1 marks

Answer: C

This question in 0653/21 Oct/Nov 2024

16 Which statement about sodium ions and chloride ions in sodium chloride is not correct? A They are strongly attracted to each other. B They both have noble gas electronic configurations. C They are arranged in a regular lattice. D They share pairs of electrons.

1 marks

Answer: D

This question in 0653/22 Feb/March 2025

19 The apparatus shown is used to test a property of compound R. lamp beaker pure water The lamp does not light when the beaker contains pure water. When compound R is dissolved in the water, the lamp lights. Which row describes compound R? type of bonding elements of compound R A covalent a metal and a non-metal B covalent non-metals only C ionic non-metals only D ionic a metal and a non-metal

1 marks

Answer: D

This question in 0653/22 Feb/March 2025

17 Which statement describes the formation of ions? A Metal atoms gain electrons to form cations and non-metal atoms lose electrons to form anions. B Metal atoms gain electrons to form anions and non-metal atoms lose electrons to form cations. C Metal atoms lose electrons to form cations and non-metal atoms gain electrons to form anions. D Metal atoms lose electrons to form anions and non-metal atoms gain electrons to form cations.

1 marks

Answer: C

This question in 0653/21 May/June 2025

15 Which statement about ions is correct? A Atoms lose or gain electrons to form ions. B Ions are held together by strong attraction between negative ions. C Ions form when atoms share electrons. D Metal ions are attracted to each other.

1 marks

Answer: A

This question in 0653/23 May/June 2025

15 Which diagram represents the lattice structure of sodium chloride? A B C D – + – – + + – – + – – – + + + + + – – – + + – – – + – – + + + +

1 marks

Answer: A

This question in 0653/22 Oct/Nov 2025

27 Crystals of pure sodium chloride are formed by crystallisation. Which row describes the structure of a sodium chloride crystal and the arrangement of the ions in the crystal? structure arrangement of ions A simple molecular random B simple molecular regular C giant lattice random D giant lattice regular

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2025