Simple molecules and covalent bonds — Paper 1 · IGCSE Science - Combined 0653

15 Which diagrams show the bonding in the molecules of carbon dioxide and ethene? carbon dioxide ethene H H A O C O C C H H H H B O C O H C C H H H H H C O C O C C H H H H D O C O H C C H H H

1 marks

Answer: C

This question in 0653/11 Oct/Nov 2005

20 The diagrams show some molecules of substances present in air. Different circles represent atoms of different elements. rw} Le} lel ie Which elements could be shown as @) and @? © = nitrogen @ = oxygen A Jv v B Jv x Cc x v D x x

1 marks

Answer: A

This question in 0653/11 Oct/Nov 2006

15 Which two elements form covalent bonds when they combine with each other? A calcium and oxygen B hydrogen and oxygen C magnesium and chlorine D sodium and chlorine

1 marks

Answer: B

This question in 0653/11 May/June 2007

18 Which elements exist as diatomic molecules? bromine calcium chlorine magnesium A v x x v B v x v x Cc x v v x D x v x v key JY correct X not correct

1 marks

Answer: B

This question in 0653/11 May/June 2007

16 Which displayed formulae correctly represent a molecule of carbon dioxide and of nitrogen? carbon dioxide, CO2 nitrogen, N2 A O–C–O N–N B O–C–O N≡N C O=C=O N–N D O=C=O N≡N

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2007

15 Which diagrams correctly show the displayed formula of ammonia and of carbon dioxide? ammonia carbon dioxide H A H N O C O H H B H N O C O H H C H N H O C O H H D H N H O C O H

1 marks

Answer: B

This question in 0653/11 May/June 2008

17 How many atoms are present in each of the molecules of the following components in air? water nitrogen noble gases oxygen vapour A 1 1 1 2 B 2 1 2 3 C 2 2 2 2 D 2 2 2 3

1 marks

Answer: B

This question in 0653/11 May/June 2008

18 A solid X is placed in the circuit shown. The lamp lights. What could solid X be? steel graphite A v v B v x Cc x v D x x

1 marks

Answer: A

This question in 0653/11 May/June 2008

16 Which gases have covalent molecules that contain one or more double bonds? carbon dioxide ethene hydrogen chloride A v v v B v v x Cc x v v D x x v

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2008

16 Which diagrams of the structures of nitrogen and ammonia are correct? W X Y Z H H N N N N H N H H N H H A W and Y B W and Z C X and Y D X and Z

1 marks

Answer: C

This question in 0653/11 May/June 2009

15 The table shows information about four different compounds. Which compound contains ionic bonds? formula of elements present compound in compound A CO2 carbon, oxygen B HCl hydrogen, chlorine C NH3 nitrogen, hydrogen D Na2O sodium, oxygen

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2010

15 Element X reacts with element Y to form compound XY. It also reacts with element Z to form compound XZ. Compound XY is an electrolyte and compound XZ is a non-electrolyte. Which row correctly shows whether elements X, Y and Z are metals or non-metals? metals non-metals A X Y, Z B X, Z Y C Y X, Z D Y, Z X

1 marks

Answer: C

This question in 0653/11 May/June 2011

17 Element X reacts with element Y to form compound XY. It also reacts with element Z to form compound XZ. Compound XY is an electrolyte and compound XZ is a non-electrolyte. Which row correctly shows whether elements X, Y and Z are metals or non-metals? metals non-metals A X Y, Z B X, Z Y C Y X, Z D Y, Z X

1 marks

Answer: C

This question in 0653/12 May/June 2011

15 A model of a molecule is shown. key = hydrogen = nitrogen Which description and formula are correct for this molecule? description formula A compound NH2 B compound N2H4 C mixture NH2 D mixture N2H4

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2011

14 A model of a molecule is shown. key = hydrogen = nitrogen Which description and formula are correct for this molecule? description formula A compound NH2 B compound N2H4 C mixture NH2 D mixture N2H4

1 marks

Answer: B

This question in 0653/12 Oct/Nov 2011

15 A model of a molecule is shown. key = hydrogen = nitrogen Which description and formula are correct for this molecule? description formula A compound NH2 B compound N2H4 C mixture NH2 D mixture N2H4

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2011

15 Two oxides have the formulae CaO and NO. Which statement about the bonding in these oxides is correct? A Both CaO and NO are covalent. B Both CaO and NO are ionic. C CaO is covalent and NO is ionic. D CaO is ionic and NO is covalent.

1 marks

This question in 0653/11 May/June 2012

15 Which statement correctly describes the bonding in compounds? A An ionic compound contains two metallic elements. B In a compound formed between a metal and a non-metal, the metal has a negative charge. C When a metal combines with a non-metal, electrons are shared between the elements. D When two non-metals combine, molecules are formed.

1 marks

Answer: D

This question in 0653/12 May/June 2012

15 Which statement correctly describes the bonding in compounds? A An ionic compound contains two metallic elements. B In a compound formed between a metal and a non-metal, the metal has a negative charge. C When a metal combines with a non-metal, electrons are shared between the elements. D When two non-metals combine, molecules are formed.

1 marks

Answer: D

This question in 0653/13 May/June 2012

25 The diagrams show molecules of four gases present in clean air. Different circles represent atoms of different elements. Which elements are shown as and ? A hydrogen nitrogen B hydrogen oxygen C oxygen hydrogen D oxygen nitrogen

1 marks

Answer: D

This question in 0653/13 May/June 2012

20 In the diagrams below, and represent different atoms. Which diagram represents molecules of a single compound? A B C D

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2013

21 Molecules of W, X and Y are shown. W X Y What are W, X and Y? W X Y A hydrogen chloride nitrogen water B hydrogen chloride water nitrogen C nitrogen hydrogen chloride water D water nitrogen hydrogen chloride

1 marks

Answer: A

This question in 0653/11 Oct/Nov 2013

26 The diagram shows a molecule of a compound of silicon and hydrogen. H H H Si Si H H H What is the molecular formula of this compound? A SiH3 B SiH4 C Si2H6 D Si6H2

1 marks

Answer: C

This question in 0653/11 Oct/Nov 2013

21 Molecules of W, X and Y are shown. W X Y What are W, X and Y? W X Y A hydrogen chloride nitrogen water B hydrogen chloride water nitrogen C nitrogen hydrogen chloride water D water nitrogen hydrogen chloride

1 marks

Answer: A

This question in 0653/12 Oct/Nov 2013

24 Which diagram represents gaseous hydrogen chloride, HCl? A B C D

1 marks

Answer: A

This question in 0653/13 Oct/Nov 2013

14 The table shows the formulae of three substances. substance formula methane CH4 water H2O oxygen O2 Which statement is correct? A Methane is made from five types of atom. B Methane, water and oxygen are molecules. C Only methane and water are molecules. D Oxygen is made from two types of atom.

1 marks

Answer: B

This question in 0653/11 May/June 2014

21 The apparatus shown is used to test a property of compound R. lamp beaker water The lamp does not light when the beaker contains pure water. When compound R is dissolved in the water, the lamp lights. Which statements about R are correct? 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 0653/12 May/June 2014

14 The table shows the formulae of three substances. substance formula methane CH4 water H2O oxygen O2 Which statement is correct? A Methane is made from five types of atom. B Methane, water and oxygen are molecules. C Only methane and water are molecules. D Oxygen is made from two types of atom.

1 marks

Answer: B

This question in 0653/13 May/June 2014

14 The structures of three molecules are shown. water ethanol methane How many atoms are in each of these molecules? water ethanol methane A 2 3 2 B 2 4 5 C 3 3 2 D 3 9 5

1 marks

Answer: D

This question in 0653/13 May/June 2015

14 Which statement about atoms and molecules is correct? A Atoms gain or lose electrons to become molecules. B Atoms of the same element contain the same number of molecules. C Molecules are the simplest unit of an atom. D Molecules contain atoms which are covalently bonded.

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2015

17 The structure of a compound is shown. H H H O O O H C C C H H H H What is the formula of this compound? A C3H5O3 B C3H6O3 C C3H8O D C3H8O3

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2015

14 and represent atoms of two different elements. X Y Which diagram represents molecules? A B C D Y Y Y Y Y Y Y X X X Y X Y X X X X Y Y Y Y Y Y Y Y X X X Y X Y X Y X X Y Y Y Y Y Y Y X X Y X Y X Y X Y Y Y Y Y Y Y X X X Y X Y X Y X Y Y Y Y Y Y Y

1 marks

Answer: C

This question in 0653/12 Oct/Nov 2015

14 The diagram represents a mixture of carbon dioxide, CO2, and carbon monoxide, CO. Which statement is correct? A The mixture contains 4 elements. B The mixture contains 4 molecules. C The mixture contains 11 elements. D The mixture contains 11 molecules.

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2015

27 Petroleum is a mixture of hydrocarbon molecules. Which row describes the method of separation of petroleum and the type of bond in hydrocarbon molecules? method of type of bond separation A distillation covalent B distillation ionic C fractional distillation covalent D fractional distillation ionic

1 marks

Answer: C

This question in 0653/12 May/June 2016

17 Which statement about compounds is correct? A An ionic compound contains two metallic elements bonded together. B In an ionic compound, metal ions are negatively charged. C When metals combine with non-metals, electrons are shared between the atoms. D When two non-metals combine, molecules are formed.

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2016

17 Which statement about compounds is correct? A An ionic compound contains two metallic elements bonded together. B In an ionic compound, metal ions are negatively charged. C When metals combine with non-metals, electrons are shared between the atoms. D When two non-metals combine, molecules are formed.

1 marks

Answer: D

This question in 0653/12 Oct/Nov 2016

17 Which statement about compounds is correct? A An ionic compound contains two metallic elements bonded together. B In an ionic compound, metal ions are negatively charged. C When metals combine with non-metals, electrons are shared between the atoms. D When two non-metals combine, molecules are formed.

1 marks

Answer: D

This question in 0653/13 Oct/Nov 2016

14 Which diagram represents molecules of hydrogen gas? A B C D

1 marks

Answer: B

This question in 0653/12 Feb/March 2017

17 Molecules of W, X and Y are shown. W X Y What are W, X and Y? W X Y A hydrogen chloride nitrogen water B hydrogen chloride water nitrogen C nitrogen hydrogen chloride water D water nitrogen hydrogen chloride

1 marks

Answer: D

This question in 0653/12 Feb/March 2017

16 Sodium and potassium are Group I metals. Chlorine and bromine are Group VII non-metals. Which statement describes the formation of a covalent bond? A Potassium and bromine combine by sharing a pair of electrons. B Sodium and chlorine combine by electron loss and gain. C Two bromine atoms combine by electron loss and gain. D Two chlorine atoms combine by sharing a pair of electrons.

1 marks

Answer: D

This question in 0653/11 May/June 2017

14 The formulae of three substances are shown. substance formula methane CH4 water H2O oxygen O2 Which statement is correct? A Methane is made from five different types of atom. B Methane, water and oxygen are molecules. C Only methane and water are molecules. D Oxygen is made from two different types of atom.

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2017

14 The formulae of three substances are shown. substance formula methane CH4 water H2O oxygen O2 Which statement is correct? A Methane is made from five different types of atom. B Methane, water and oxygen are molecules. C Only methane and water are molecules. D Oxygen is made from two different types of atom.

1 marks

Answer: B

This question in 0653/12 Oct/Nov 2017

14 The formulae of three substances are shown. substance formula methane CH4 water H2O oxygen O2 Which statement is correct? A Methane is made from five different types of atom. B Methane, water and oxygen are molecules. C Only methane and water are molecules. D Oxygen is made from two different types of atom.

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2017

17 One molecule of a compound contains twice as many carbon atoms as oxygen atoms, and three times as many hydrogen atoms as carbon atoms. What is the formula of this compound? A C2H3O B C2H6O C C2H6O2 D C4H6O2

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2017

14 Which statement about atoms and molecules is correct? A Atoms gain or lose electrons to become molecules. B Atoms of the same element contain the same number of molecules. C Molecules are the simplest unit of an atom. D Molecules contain atoms which are covalently bonded.

1 marks

Answer: D

This question in 0653/12 Feb/March 2018

18 The diagram represents molecules of phosphine. H H H P P H H H H H H P P H H H What is the formula of a molecule of phosphine? A HP B HP3 C PH3 D P4H12

1 marks

Answer: C

This question in 0653/11 May/June 2018

18 Which formula represents a molecule that contains three different elements? A CO2 B H2O C O3 D NOCl

1 marks

Answer: D

This question in 0653/12 May/June 2018

14 The diagrams represent different substances. P Q R S T Which row describes the substances? only separate mixture of atoms only molecules atoms and molecules A P Q S B Q T R C T P R D T Q P

1 marks

Answer: A

This question in 0653/13 May/June 2018

18 Which formula represents a molecule that contains three different elements? A CO2 B H2O C O3 D NOCl

1 marks

Answer: D

This question in 0653/13 May/June 2018

14 The diagram represents a mixture of carbon dioxide, CO2, and carbon monoxide, CO. Which statement is correct? A The mixture contains 4 elements. B The mixture contains 4 molecules. C The mixture contains 11 elements. D The mixture contains 11 molecules.

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2018

16 Which compound contains covalent bonds? A CuCl 2 B HCl C KCl D MgCl 2

1 marks

Answer: B

This question in 0653/12 Feb/March 2019

14 A molecule of hydrogen has the formula H2. A molecule of a protein contains several different elements. Which statement about these molecules is correct? A They both contain cations and anions bonded together. B They both contain different types of atom. C They both contain more than one atom bonded together. D They both contain only one type of atom.

1 marks

Answer: C

This question in 0653/12 May/June 2019

16 Which row about each substance is correct? type of description other substance bonding of bonds information A ammonia covalent three shared all atoms have pairs of electrons full outer electron shells B lithium fluoride covalent one shared both atoms have pair of electrons noble gas electronic structure C potassium iodide ionic electron transfer from volatile potassium to iodine compound D water ionic electron transfer from non-volatile hydrogen to oxygen compound

1 marks

Answer: A

This question in 0653/12 May/June 2019

14 Which row identifies a substance that exists only as separate atoms and a substance that exists as a molecule? separate atoms molecule A helium methane B hydrogen helium C neon argon D oxygen carbon dioxide

1 marks

Answer: A

This question in 0653/11 May/June 2020

14 Which term describes ammonia, NH3? A element B ion C atom D molecule

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2020

16 Which statement about non-metals is correct? A They are in Group I of the Periodic Table. B They are malleable and have high melting points. C They react with acids to form hydrogen gas. D They react with other non-metals to form covalent compounds.

1 marks

Answer: D

This question in 0653/13 Oct/Nov 2020

16 Which row about elements and compounds is correct? elements compounds A are metals only contain ionic or covalent bonds B are non-metals only contain covalent bonds only C are metals or non-metals contain ionic bonds only D are metals or non-metals contain ionic or covalent bonds

1 marks

Answer: D

This question in 0653/11 May/June 2021

17 Which groups of the Periodic Table form compounds containing covalent bonds? A Group I and Group 0 B Group I and Group VII C Group V and Group 0 D Group V and Group VII

1 marks

Answer: D

This question in 0653/11 May/June 2022

17 Which substance contains covalent bonds? A CH4 B KOH C NaCl D PbBr2

1 marks

Answer: A

This question in 0653/12 May/June 2022

14 Which statement describes a molecule? A It consists of one nucleus surrounded by electrons. B It consists of two or more atoms bonded together. C It has a negative charge because it has gained electrons. D It has a positive charge because it has lost electrons.

1 marks

Answer: B

This question in 0653/13 May/June 2022

17 Which compound contains covalent bonds? A HCl B NaCl C KCl D CaCl 2

1 marks

Answer: A

This question in 0653/13 May/June 2022

14 The structures of three molecules are shown. water ethanol methane How many atoms are in each molecule? water ethanol methane A 2 3 2 B 2 4 5 C 3 3 2 D 3 9 5

1 marks

Answer: D

This question in 0653/12 Feb/March 2023

14 The formulae of three substances are shown. substance formula methane CH4 water H2O oxygen O2 Which statement is correct? A Methane is made from five different types of atom. B Methane, water and oxygen are molecules. C Only methane and water are molecules. D Oxygen is made from two different types of atom.

1 marks

Answer: B

This question in 0653/12 May/June 2023

23 Read the sentences about calcium, copper and bromine. Calcium, copper and bromine are in the same period of the Periodic Table. The metals react with bromine to form calcium bromide and copper(II) bromide. From the position of these elements in the Periodic Table, it can be predicted that the bonding in the metal bromides is … 1 … and that … 2 … coloured. The formula of calcium bromide is … 3 … . Which words correctly complete gaps 1, 2 and 3? 1 2 3 A covalent both bromides are CaBr B covalent only copper(II) bromide is CaBr2 C ionic both bromides are CaBr D ionic only copper(II) bromide is CaBr2

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2023

14 Substance X is an element. It is a gas at room temperature. It is made of X2 molecules. Which diagram represents X? A B C D

1 marks

Answer: C

This question in 0653/12 Oct/Nov 2023

14 Substance X is an element. It is a gas at room temperature. It is made of X2 molecules. Which diagram represents X? A B C D

1 marks

Answer: C

This question in 0653/13 Oct/Nov 2023

16 Which row about elements and compounds is correct? elements compounds A are metals only contain ionic or covalent bonds B are non-metals only contain covalent bonds only C are metals or non-metals contain ionic bonds only D are metals or non-metals contain ionic or covalent bonds

1 marks

Answer: D

This question in 0653/13 May/June 2024

17 Which dot-and-cross diagram represents the outer shell electrons in a water molecule? A B C D O O O O H H H H H H H H

1 marks

Answer: A

This question in 0653/13 May/June 2024

15 Potassium and iodine react together to form potassium iodide, KI. Which statement is correct? A Ionic bonds form between neutral ions. B The potassium and iodine atoms share a pair of electrons to form a covalent bond. C The potassium and iodine atoms share a pair of electrons to form an ionic bond. D The potassium atom loses an electron to form a positive ion.

1 marks

Answer: D

This question in 0653/11 May/June 2025

15 Which molecule contains the lowest number of outer-shell electrons? A Cl 2 B CH4 C H2 D H2O

1 marks

Answer: C

This question in 0653/12 May/June 2025

20 Which substance contains a covalent bond between two different elements? A chlorine B potassium chloride C hydrogen D hydrogen chloride

1 marks

Answer: D

This question in 0653/13 May/June 2025

15 Which compound contains covalent bonds? A LiI B HCl C KCl D NaBr

1 marks

Answer: B

This question in 0653/12 Oct/Nov 2025

15 Which compound contains covalent bonds? A LiI B HCl C KCl D NaBr

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2025