Shapes of molecules — Paper 1 · A Level Chemistry 9701

32 Which molecules are planar? 1 BCl3 2 NH3 3 PH3

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2005

6 Lycra is a polyurethane fibre used in the fashion industry. It is a polymer made from two monomers, one of which has the following formula. O=C=N–(CH2)n –N=C=O What is the O–C–N bond angle in this molecule? A 90 ° B 109 ° C 120 ° D 180 °

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2007

5 In this question, the methyl group, CH3, is represented by Me. Trimethylamine, Me3N, reacts with boron trifluoride, BF3, to form a compound of formula Me3N.BF3. How may this reaction be written in terms of the shapes of the reactants and products? Me Me Me Me F N A Me Me + F B F N F F B F Me Me N Me B Me B Me Me + B F F N F F F F Me Me Me Me F N C Me Me + F B N F B F F F Me Me Me Me B N D Me Me + F F N F B F F F

1 marks

Answer: C

This question in 9701/11 May/June 2008

22 Chloroethene, CH2=CHCl, is the monomer of PVC. What are the C−C−C bond angles along the polymeric chain in PVC? A They are all 109.5°. B Half are 109.5° and half are 120°. C They are all 120°. D They are all 180°.

1 marks

Answer: A

This question in 9701/11 May/June 2008

4 The antidote molecule shown can help to prevent liver damage if someone takes too many paracetamol tablets. H H H x y represents a H S C C N lone pair z H H H What is the order of decreasing size of the bond angles x, y and z? largest smallest A x y z B x z y C y z x D z y x

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2009

9 PCl5 dissociates as follows. PCl5(g) → PCl3(g) + Cl2(g) The extent of dissociation is 13 % at 160 °C and 100 % at 300 °C. Which pair of statements about this formation of PCl3 is correct? shape of PCl3 molecule the reaction is A pyramidal endothermic B pyramidal exothermic C trigonal endothermic D trigonal exothermic

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2009

32 Which physical properties are due to hydrogen bonding between water molecules? 1 Water has a higher boiling point than H2S. 2 Ice floats on water. 3 The H−O−H bond angle in water is approximately 104°.

1 marks

Answer: B

This question in 9701/11 Oct/Nov 2009

7 Organic nitrates in photochemical smog can cause breathing difficulties. The diagram shows an example of an organic nitrate molecule. H 1 3 H C C O O NO2 2 H O What is the correct order of the bond angles shown in ascending order (smallest first)? A 1 → 2 → 3 B 2 → 1 → 3 C 3 → 1 → 2 D 3 → 2 → 1

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2010

36 Element X is a solid. It occurs as a contaminant of carbonaceous fuels. Its oxide Y is formed in car engines. Further oxidation of Y to Z can occur in the atmosphere. Which statements about Y and Z are correct? 1 Molecule Y has lone pairs of electrons. 2 The atmospheric oxidation of Y to Z is a catalysed reaction. 3 Y is a colourless gas.

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2010

10 Which molecule or structure does not contain three atoms bonded at an angle between 109° and 110°? A ethanoic acid B graphite C propane D silicon(IV) oxide

1 marks

Answer: B

This question in 9701/12 Oct/Nov 2010

6 Organic nitrates in photochemical smog can cause breathing difficulties. The diagram shows an example of an organic nitrate molecule. H 1 3 H C C O O NO2 2 H O What is the correct order of the bond angles shown in ascending order (smallest first)? A 1 → 2 → 3 B 2 → 1 → 3 C 3 → 1 → 2 D 3 → 2 → 1

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2010

37 Which descriptions of the ammonium ion are correct? 1 It contains ten electrons. 2 It has a bond angle of 109.5°. 3 It has only three bonding pairs of electrons.

1 marks

Answer: B

This question in 9701/11 May/June 2011

34 Which descriptions of the ammonium ion are correct? 1 It contains ten electrons. 2 It has a bond angle of 109.5°. 3 It has only three bonding pairs of electrons.

1 marks

Answer: B

This question in 9701/13 May/June 2011

4 Methyl isocyanate, CH3NCO, is a toxic liquid which is used in the manufacture of some pesticides. In the methyl isocyanate molecule, the sequence of atoms is H3C — N C O. What is the approximate angle between the bonds formed by the N atom? A B C D N C O N C O N C O H3C N C O H3C H3C H3C 104° 109° 120° 180°

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2011

31 Which statements about bond angles are correct? 1 The bond angle in SO2 is smaller than the bond angle in CO2. 2 The bond angle in H2O is smaller than the bond angle in CH4. 3 The bond angle in NH3 is smaller than the bond angle in BF3.

1 marks

This question in 9701/12 Oct/Nov 2011

5 Methyl isocyanate, CH3NCO, is a toxic liquid which is used in the manufacture of some pesticides. In the methyl isocyanate molecule, the sequence of atoms is H3C — N C O. What is the approximate angle between the bonds formed by the N atom? A B C D N C O N C O N C O H3C N C O H3C H3C H3C 104° 109° 120° 180°

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2011

3 What is the most likely shape of a molecule of hydrazine, N2H4? A B C D H H H H H H H 90° 90° 120° 107° H N N H N N H N N N N H H H H H H

1 marks

Answer: D

This question in 9701/12 May/June 2012

31 Which of the following molecules and ions have a regular trigonal planar shape? 1 BF3 2 CH3 + 3 Al Cl 3

1 marks

Answer: A

This question in 9701/12 May/June 2012

3 Sodium borohydride, NaBH4, and boron trifluoride, BF3, are compounds of boron. What are the shapes around boron in the borohydride ion and in boron trifluoride? borohydride ion boron trifluoride A square planar pyramidal B square planar trigonal planar C tetrahedral pyramidal D tetrahedral trigonal planar

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2012

12 In which pair do the molecules have the same shape as each other? A H2O and CO2 B H2O and SCl 2 C NH3 and BH3 D SCl 2 and BeCl 2

1 marks

Answer: B

This question in 9701/11 Oct/Nov 2012

3 Sodium borohydride, NaBH4, and boron trifluoride, BF3, are compounds of boron. What are the shapes around boron in the borohydride ion and in boron trifluoride? borohydride ion boron trifluoride A square planar pyramidal B square planar trigonal planar C tetrahedral pyramidal D tetrahedral trigonal planar

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2012

12 In which pair do the molecules have the same shape as each other? A H2O and CO2 B H2O and SCl 2 C NH3 and BH3 D SCl 2 and BeCl 2

1 marks

Answer: B

This question in 9701/12 Oct/Nov 2012

16 In a car engine, non-metallic element X forms a pollutant oxide Y. Y can be further oxidised to Z. Two students made the following statements. Student P The molecule of Y contains lone pairs of electrons. Student Q The oxidation number of X increases by 1 from Y to Z. X could be carbon or nitrogen or sulfur. Which student could be correct if X were any of these elements? A P only B Q only C both P and Q D neither P nor Q

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2012

11 Which molecule is planar? A C2Cl 4 B C3H6 C C3H8 D NF3

1 marks

Answer: A

This question in 9701/13 Oct/Nov 2012

33 Valence shell electron pair repulsion theory should be used to answer this question. Which species are trigonal planar? 1 BH3 2 CH3 + 3 PH3

1 marks

Answer: B

This question in 9701/11 May/June 2013

9 Dicarbon monoxide, C2O, is found in dust clouds in space. Analysis of it shows that the sequence of atoms in this molecule is C – C – O. All bonds are double bonds and there are no unpaired electrons. How many lone pairs of electrons are present in a molecule of C2O? A 1 B 2 C 3 D 4

1 marks

Answer: C

This question in 9701/12 May/June 2013

17 Which statement about ammonia is completely correct? A Ammonia acts as a nucleophile by accepting a pair of electrons when it reacts with bromoethane. B Ammonia can form a co-ordinate bond with a hydrogen ion to form an ammonium ion. C Ammonia is a base and accepts hydroxide ions. D The shape of the ammonia molecule is pyramidal with bond angles of 109.5°.

1 marks

Answer: B

This question in 9701/12 May/June 2013

6 Al Cl 3 vapour forms molecules with formula Al 2Cl 6 as it is cooled. What happens to the bond angles during the change from Al Cl 3 to Al 2Cl 6? A Some decrease, some remain the same. B Some increase, some remain the same. C They all decrease. D They all increase.

1 marks

Answer: C

This question in 9701/11 May/June 2014

9 Which molecular structure will have the smallest overall dipole? A B C D H3C Cl H3C Cl Cl Cl Cl CH3 C C C C C C C C Cl H2C H H3C Cl H3C CH3 H3C Cl

1 marks

Answer: D

This question in 9701/11 May/June 2014

31 Use of the Data Booklet is relevant to this question. When the liquid N2F4 is heated, it decomposes into a single product, X. Which statements are correct? 1 N – F bonds are broken during this decomposition. 2 The enthalpy change when N2F4 decomposes into X is approximately +160 kJ mol–1. 3 Molecules of X are non-linear.

1 marks

Answer: C

This question in 9701/11 May/June 2014

10 X is an element in Period 2. In which fluoride is the F – X – F angle the largest? A BF3 B CF4 C NF3 D OF2

1 marks

Answer: A

This question in 9701/13 May/June 2014

32 Urea is a product of animal metabolism. It can also be used as a fertiliser. H x N H O C H N H urea The diagram shows angle x in this molecule. Which statements about the structure of urea are correct? 1 Angle x is approximately 120°. 2 The molecule has two π bonds. 3 The molecule has only three lone pairs of electrons.

1 marks

Answer: D

This question in 9701/11 May/June 2015

17 Which statement about the ammonium ion, NH4 +, is correct? A All bond angles are 107°. B Ammonium ions are formed when ammonia behaves as an acid. C Ammonium ions are unreactive when heated with NaOH(aq). D The bonds are all the same length.

1 marks

Answer: D

This question in 9701/12 May/June 2015

36 Which descriptions of the ammonium ion are correct? 1 It contains ten electrons. 2 It has a bond angle of 109.5°. 3 It has only three bonding pairs of electrons.

1 marks

This question in 9701/12 Oct/Nov 2015

6 Which series shows molecules in order of increasing bond angle? A CH4 → BF3 → NH3 B H2O → CO2 → BF3 C NH3 → CH4 → CO2 D NH3 → CH4 → H2O

1 marks

Answer: C

This question in 9701/12 Feb/March 2016

15 Which row of the table is correct? shape bonds present ammonia ammonium ammonia ammonium molecule ion molecule ion A pyramidal regular tetrahedral σ σ B pyramidal regular tetrahedral σ π C regular tetrahedral pyramidal σ σ D regular tetrahedral pyramidal π σ

1 marks

Answer: A

This question in 9701/12 Feb/March 2016

31 Which molecules have an overall dipole moment? 1 carbon monoxide, CO 2 phosphine, PH3 3 carbon dioxide, CO2

1 marks

Answer: B

This question in 9701/12 Feb/March 2016

18 Which statement about the ammonia molecule and/or the ammonium ion is correct? A Ammonia molecules are basic because they can donate H+ ions. B Ammonium ions are basic because they can accept H+ ions. C If ammonium ions are heated with NaOH(aq), ammonia molecules are formed. D The bond angle in NH4 + is 2.5° less than the bond angle in NH3.

1 marks

Answer: C

This question in 9701/11 May/June 2016

5 Each of the four species in this question are isolated and gaseous. Which species is not planar? A BF3 B CH3 + C C2H4 D NH3

1 marks

Answer: D

This question in 9701/12 May/June 2016

7 Methyl isocyanate, CH3NCO, is a toxic liquid which is used in the manufacture of some pesticides. What is the approximate angle between the bonds formed by the N atom in a molecule of methyl isocyanate? A B C D N C O N C O N C O H3C N C O H3C H3C H3C 104° 109° 120° 180°

1 marks

Answer: C

This question in 9701/13 May/June 2016

36 Ammonia is a colourless gas that is produced by the Haber process. Which statements about ammonia are correct? 1 An ammonia molecule has three bond pairs and one lone pair of electrons. 2 If ammonia is bubbled into water the pH of the solution will increase. 3 Ammonia gas can be made by warming ammonium sulfate with aqueous hydrochloric acid.

1 marks

Answer: B

This question in 9701/13 May/June 2016

6 Histamine is produced in the body to help fight infection. Its shape allows it to fit into receptors which expand blood vessels. H H H N C H x N C C C N y z H C H H H H histamine What are the bond angles x, y and z in histamine, from the smallest to the largest? smallest largest bond angle bond angle A x y z B y x z C y z x D z y x

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2016

6 Histamine is produced in the body to help fight infection. Its shape allows it to fit into receptors which expand blood vessels. H H H N C H x N C C C N y z H C H H H H histamine What are the bond angles x, y and z in histamine, from the smallest to the largest? smallest largest bond angle bond angle A x y z B y x z C y z x D z y x

1 marks

Answer: A

This question in 9701/13 Oct/Nov 2016

6 Which reaction involves a decrease in the bond angle at a carbon atom? A bromoethane refluxed with ethanolic sodium hydroxide B complete combustion of methane in air C ethanol heated with conc. H2SO4 D polymerisation of ethene

1 marks

Answer: D

This question in 9701/12 May/June 2017

4 Two conversions are shown. NH4 + → NH3 C2H4 → C2H6 Which similar feature do these two conversions have? A change in oxidation state of an element B decrease in bond angle C formation of a lone pair of electrons D loss of a π bond

1 marks

Answer: B

This question in 9701/13 May/June 2017

3 In which structure are three atoms bonded together in a straight line? A poly(ethene), ] ( CH2CH2 ) n B propane, C3H8 C silicon tetrachloride, SiCl4 D sulfur hexafluoride, SF6

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2017

4 Ethane burns in oxygen to produce carbon dioxide and water vapour. Which bond angles are present in the molecules of ethane and its combustion products? ethane combustion products A 90° 104.5° and 180° B 90° 109.5° and 120° C 109.5° 104.5° and 180° D 109.5° 109.5° and 180°

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2017

3 In which structure are three atoms bonded together in a straight line? A poly(ethene), ] ( CH2CH2 ) n B propane, C3H8 C silicon tetrachloride, SiCl4 D sulfur hexafluoride, SF6

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2017

1 What are the shapes of the molecules of water and boron trifluoride? H2O BF3 A linear pyramidal B linear trigonal C non-linear pyramidal D non-linear trigonal

1 marks

Answer: D

This question in 9701/12 Feb/March 2018

5 Which molecule has no overall dipole? A CH3Cl B CH2Cl 2 C CHCl 3 D CCl 4

1 marks

Answer: D

This question in 9701/11 May/June 2018

32 Which molecules and ions have a bond angle of 120°? 1 BF3 2 CH3 – 3 NH3

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2018

4 In which set do all the molecules have all their atoms arranged in one plane? A Al Cl 3, BF3, PH3 B Al Cl 3, CO2, NH3 C BF3, C2H4, C3H6 D C2H4, CO2, H2O

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2018

32 Which molecules and ions have a bond angle of 120°? 1 BF3 2 CH3 – 3 NH3

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2018

4 The eight species that follow all have covalent bonds. In which pair do the species have different shapes from each other? A BeCl 2 and CO2 B CH4 and NH4 + C NH3 and BF3 D SCl 2 and H2O

1 marks

Answer: C

This question in 9701/12 Feb/March 2019

5 Histidine is an amino acid. histidine H 2 H H 1 H N O C H N C C C C 3 C N H H O H H What are the approximate bond angles 1, 2, and 3? 1 2 3 A 109.5 107 90 B 120 107 109.5 C 120 120 90 D 120 120 109.5

1 marks

Answer: B

This question in 9701/12 Feb/March 2019

5 In which species is there a lone pair of electrons? A CH3 B CH3 + C CH3 – D CH4

1 marks

Answer: C

This question in 9701/11 May/June 2019

19 Which statement is correct? A Ammonia reacts with alkalis to form the ammonium ion. B Ammonium chloride contains ionic, covalent and co-ordinate bonds. C The ammonium ion reacts with acids to produce ammonia. D The bond angle in the ammonium ion is approximately 107°.

1 marks

Answer: B

This question in 9701/11 May/June 2019

18 Which statement about the ammonium ion is correct? A It can act as a Brønsted-Lowry base. B It can react with OH– to give ammonia. C It is pyramidal with bond angles of 107°. D The nitrogen atom is sp2 hybridised.

1 marks

Answer: B

This question in 9701/13 May/June 2019

3 Which molecule or ion contains the smallest bond angle? A C2H4 B CH3COCH3 C NH4 + D NH3

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2019

19 Ammonia, carbon dioxide and water react together to form ammonium carbonate. Which statement about this reaction is correct? A It is a redox reaction. B It is an acid-base reaction. C The H–N–H bond angle decreases as a consequence of this reaction. D The three substances react in a 1 : 1 : 1 ratio in this reaction.

1 marks

Answer: B

This question in 9701/12 Oct/Nov 2019

31 Which gaseous molecules are polar? 1 ammonia 2 hydrogen sulfide 3 boron trifluoride

1 marks

Answer: B

This question in 9701/12 Oct/Nov 2019

36 Which statements about ammonia are correct? 1 An ammonia molecule has three bond pairs and one lone pair of electrons. 2 When ammonia is bubbled into water the pH of the solution increases. 3 Ammonia gas can be made by warming ammonium sulfate with aqueous hydrochloric acid.

1 marks

Answer: B

This question in 9701/12 Oct/Nov 2019

3 Which molecule or ion contains the smallest bond angle? A C2H4 B CH3COCH3 C NH4 + D NH3

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2019

3 Which molecule does not have any 90° or 180° bond angles? A C2H6 B CO2 C PF5 D SF6

1 marks

Answer: A

This question in 9701/12 Feb/March 2020

39 Which statements apply to tetrafluoromethane? 1 It is rapidly decomposed by ultraviolet radiation. 2 It is less harmful to the ozone layer than dichlorodifluoromethane. 3 It is a non-polar molecule.

1 marks

Answer: C

This question in 9701/12 Feb/March 2020

24 Poly(propene) is an addition polymer. What are the C–C–C bond angles along its polymer chain? A They are all 109°. B Half of them are 109° and half are 120°. C Half of them are 90° and half are 180°. D They are all 120°.

1 marks

Answer: A

This question in 9701/11 May/June 2020

32 Which molecules have no overall dipole moment? 1 boron trifluoride 2 methane 3 phosphorus pentafluoride

1 marks

Answer: A

This question in 9701/11 May/June 2020

17 Ammonia can undergo an acid–base reaction with hydrogen chloride to form ammonium chloride. Which statement is correct? A The ammonium ion is basic. B The hydrogen atom from HCl donates a lone pair of electrons to the nitrogen atom. C The H–N–H bond angle in ammonia is the same as the H–N–H bond angle in the ammonium ion. D The H–N–H bond angle in the ammonium ion is the same as the H–C–H bond angle in methane.

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2020

4 The structure of compound A is shown. compound A CH3 CH3 CH CH C CH C CH CH2OH CH3 CH3 Some of the carbon atoms in compound A have a tetrahedral arrangement of bonds. Some of the carbon atoms in compound A have a trigonal planar arrangement of bonds. How many carbon atoms are there of each type? tetrahedral trigonal planar A 5 12 B 8 8 C 9 6 D 9 8

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2020

15 Water and ammonia take part in a reaction that produces the ammonium ion. Which statement about this reaction is correct? A The ammonia molecule and the ammonium ion do not have dipole moments. B The bond angle changes from 109.5° in the ammonia molecule to 107° in the ammonium ion. C The reaction is a redox reaction. D The water is acting as an acid.

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2020

17 Ammonia can undergo an acid–base reaction with hydrogen chloride to form ammonium chloride. Which statement is correct? A The ammonium ion is basic. B The hydrogen atom from HCl donates a lone pair of electrons to the nitrogen atom. C The H–N–H bond angle in ammonia is the same as the H–N–H bond angle in the ammonium ion. D The H–N–H bond angle in the ammonium ion is the same as the H–C–H bond angle in methane.

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2020

3 Phosphorus forms two chlorides. Phosphorus(III) chloride, PCl 3, is a covalent liquid. Phosphorus(V) chloride is an ionic solid. One of the ions present is [PCl 4]+. What is the shape of the PCl 3 molecule and the [PCl 4]+ ion? PCl 3 [PCl 4]+ A pyramidal square planar B pyramidal tetrahedral C tetrahedral square planar D trigonal planar tetrahedral

1 marks

Answer: B

This question in 9701/11 May/June 2021

34 Which molecules contain at least one bond angle of 120? 1 C2H4 2 PF5 3 NCl 3

1 marks

Answer: B

This question in 9701/11 May/June 2021

4 The structural formula of alliin is shown. alliin H H O NH2 y z x C C CH2 S CH2 C H H CO2H What are the approximate bond angles x, y and z in a molecule of alliin? x y z A 90 90 109 B 120 109 90 C 120 120 109 D 180 109 109

1 marks

Answer: C

This question in 9701/12 May/June 2021

4 Ethanal reacts with hydroxylamine, NH2OH, to form the molecule shown. H H y z H C C N O H x H What is the order of increasing bond angle in this structure from smallest to largest? A z, x, y B y, z, x C x, z, y D z, y, x

1 marks

Answer: A

This question in 9701/13 May/June 2021

37 The diagram shows a molecule of a compound used as a flame retardant. Br Br Br Br Br Br Which statements about this structure are correct? 1 Each brominated C atom is chiral. 2 The molecular formula is C12H20Br6. 3 The C–C–C bond angles are all 120.

1 marks

Answer: D

This question in 9701/13 May/June 2021

18 Which row is correct? shape bonds present ammonia ammonium ammonia ammonium molecule ion molecule ion A pyramidal regular tetrahedral   B pyramidal regular tetrahedral   C regular tetrahedral pyramidal   D regular tetrahedral pyramidal  

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2021

5 Atom X is the central atom in a molecule. In this molecule, atom X has four pairs of valence electrons in its outer shell. The four pairs of valence electrons include at least one bond pair and at least one lone pair. What could be a possible shape for the molecule? A linear B non-linear C trigonal bipyramidal D trigonal planar

1 marks

Answer: B

This question in 9701/12 Oct/Nov 2021

34 When the liquid N2F4 is heated, it decomposes into a single product, X. Which statements are correct? 1 N–F bonds are broken during this decomposition. 2 The enthalpy change when N2F4 decomposes into X is approximately +160 kJ mol–1. 3 Molecules of X are non-linear.

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2021

18 Which row is correct? shape bonds present ammonia ammonium ammonia ammonium molecule ion molecule ion A pyramidal regular tetrahedral   B pyramidal regular tetrahedral   C regular tetrahedral pyramidal   D regular tetrahedral pyramidal  

1 marks

Answer: A

This question in 9701/13 Oct/Nov 2021

5 In which structure are three atoms bonded together in a straight line? A poly(ethene), ] ( CH2CH2 ) n B propane, C3H8 C silicon tetrachloride, SiCl 4 D sulfur hexafluoride, SF6

1 marks

Answer: D

This question in 9701/11 May/June 2022

6 VSEPR theory should be used to answer this question. Hydrazine has the following structure. hydrazine H H X N N H H What is the predicted bond angle X? A 90 B 107 C 109.5 D 120

1 marks

Answer: B

This question in 9701/13 May/June 2022

6 Which molecule has an equal number of bonding electrons and lone-pair electrons? A BH3 B CO2 C F2O D SO2

1 marks

Answer: B

This question in 9701/11 Oct/Nov 2022

23 Which statement about ammonia or the ammonium ion is correct? A Ammonia gas is produced when an aqueous solution containing the ammonium ion is reacted with a strong acid. B Silver iodide is soluble in a concentrated aqueous solution of ammonia. C The ammonium ion has the same number of electrons as a methane molecule. D The square planar ammonium ion contains a dative covalent bond.

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2022

13 VSEPR theory should be used in answering this question. The dot-and-cross diagram for an ozone, O3, molecule is shown. O O O What is the predicted bond angle in this molecule? A 107 B 109.5 C 117 D 120

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2022

6 Which molecule has an equal number of bonding electrons and lone-pair electrons? A BH3 B CO2 C F2O D SO2

1 marks

Answer: B

This question in 9701/13 Oct/Nov 2022

8 In which species is there a lone pair of electrons? A CH3 B CH3 + C CH3 – D CH4

1 marks

Answer: C

This question in 9701/12 Feb/March 2023

5 Ammonia reacts with acids to form the ammonium ion. NH, + H’ = NH, Which row is correct? + bond angle shape of NH, in NH,*/° A pyramidal 107 B pyramidal 109.5 Cc tetrahedral 107 D tetrahedral 109.5

1 marks

Answer: D

This question in 9701/13 May/June 2023

6 Which row is correct? shape of H3O+ shape of SCl 2 A pyramidal non-linear B pyramidal linear C trigonal planar non-linear D trigonal planar linear When an evacuated tube of volume 400cm3 is filled with gas at 300K and 101kPa, the mass of

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2023

5 Ammonium ions, NH4 +, are formed when ammonia gas reacts with hydrogen chloride gas. Which statement about the changes that occur in this reaction is correct? A The dipole moment of an ammonium ion is greater than the dipole moment of an ammonia molecule. B The H−N−H bond angle decreases when an ammonium ion is formed. C The hybridisation of nitrogen does not change. D There is electron transfer from nitrogen to chlorine.

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2023

7 Two compounds of boron are sodium borohydride, NaBH4, and boron trifluoride, BF3. What are the shapes of the borohydride ion and the boron trifluoride molecule? borohydride ion boron trifluoride A square planar pyramidal B square planar trigonal planar C tetrahedral pyramidal D tetrahedral trigonal planar In an experiment, 0.100mol of propan-1-ol is burnt completely in 12.0dm3 of oxygen, measured at

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2023

6 Which row is correct? shape of H3O+ shape of SCl 2 A pyramidal non-linear B pyramidal linear C trigonal planar non-linear D trigonal planar linear When an evacuated tube of volume 400cm3 is filled with gas at 300K and 101kPa, the mass of

1 marks

Answer: A

This question in 9701/13 Oct/Nov 2023

6 Aluminium chloride exists as Al 2Cl 6 molecules at room temperature. When heated to a high temperature, Al Cl 3 molecules are formed. What are the arrangements of the bonding pairs of electrons around the aluminium atom in the two forms of aluminium chloride? Al Cl 3 Al 2Cl 6 A planar planar B planar tetrahedral C tetrahedral tetrahedral D tetrahedral octahedral

1 marks

Answer: B

This question in 9701/12 Feb/March 2024

6 The structure of the sulfur dioxide molecule is shown. O S O What is the shape of the sulfur dioxide molecule? A linear B non-linear C pyramidal D tetrahedral

1 marks

Answer: B

This question in 9701/11 May/June 2024

24 What is the bond angle in the ammonium ion? A 90 B 107 C 109.5 D 120

1 marks

Answer: C

This question in 9701/11 May/June 2024

5 Which shape is correctly predicted by VSEPR theory? number of bonded number of shape electron pairs lone pairs A 2 2 linear B 2 2 tetrahedral C 3 1 pyramidal D 3 1 trigonal planar

1 marks

Answer: C

This question in 9701/12 May/June 2024

22 Which statement describes a property of an ammonium ion? A An aqueous ammonium ion is a weak Brønsted–Lowry base. B Aqueous ammonium sulfate reacts with dilute hydrochloric acid to make ammonia gas. C An ammonium ion has a pyramidal shape with an H–N–H bond angle of 107. D The four N–H covalent bonds in an ammonium ion are identical to each other.

1 marks

Answer: D

This question in 9701/12 May/June 2024

5 Arsenic forms a compound with fluorine. In this compound, the arsenic atom has no lone pair of electrons and there are no dative bonds. Selenium also forms a compound with fluorine. In this compound, the selenium atom has no lone pair of electrons and there are no dative bonds. In which compounds are there two different bond angles? (In this question, 180 bond angles should be ignored.) A both arsenic fluoride and selenium fluoride B arsenic fluoride only C selenium fluoride only D neither arsenic fluoride nor selenium fluoride

1 marks

Answer: B

This question in 9701/13 May/June 2024

6 A structure for borazole, N3B3H6, is shown. borazole H H B – N+ H N+ B – H B – N+ H H Which shape is borazole and how many  electrons are there in the structure? number of shape  electrons A non-planar 3 B non-planar 6 C planar 3 D planar 6

1 marks

Answer: D

This question in 9701/13 May/June 2024

23 NH4Cl reacts with NaOH in an aqueous solution. Which statement is correct? A The reaction gives rise to two different polar product molecules. B The bond angle in the nitrogen-containing species remains unchanged. C The ammonium ion acts as a base. D The oxidation state of nitrogen increases in the reaction.

1 marks

Answer: A

This question in 9701/13 May/June 2024

5 Phosphorus forms a compound with hydrogen called phosphine, PH3. This compound can react with a hydrogen ion, H+. Which type of interaction occurs between PH3 and H+? A dative covalent bond B dipole–dipole forces C hydrogen bond D ionic bond

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2024

5 An ion contains 1 nitrogen atom and 2 hydrogen atoms. It has an H–N–H bond angle of approximately 105. Which row is correct? number of lone overall charge pairs around on ion N in ion A 1 +1 B 2 +1 C 1 –1 D 2 –1

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2024

24 Three statements about ammonia molecules and ammonium ions are given. 1 In aqueous solution, ammonia molecules form coordinate bonds with hydroxide ions. 2 Ammonium ions are Brønsted–Lowry acids. 3 The H–N–H bond angle is larger in the ammonium ion than in the ammonia molecule. Which statements are correct? A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2024

5 The structure of the hormone histamine is shown. histamine H H H N C H x N C C C N y z H C H H H H Which row contains the bond angles x, y and z in histamine in the correct order from the smallest to the largest? smallest largest bond angle bond angle A x y z B y x z C y z x D z y x

1 marks

Answer: A

This question in 9701/12 Feb/March 2025

15 In which pair do both species: ● have the same shape ● have the same number of covalent bonds? A methane and the ammonium ion B carbon dioxide and nitrogen C boron trifluoride and ammonia D water and oxygen

1 marks

Answer: A

This question in 9701/11 May/June 2025

7 Which row is correct? smallest largest bond angle bond angle A H2O NH3 BF3 B BF3 NH3 H2O C NH3 H2O BF3 D H2O BF3 NH3

1 marks

Answer: A

This question in 9701/12 May/June 2025

11 BF3 reacts with NH3 to form a single compound with a simple molecular structure. BF3 + NH3 F3B–NH3 Which row describes how the bond angles change during the reaction? F–B–F bond angle H–N–H bond angle A decreases decreases B decreases increases C increases decreases D increases increases

1 marks

Answer: B

This question in 9701/13 May/June 2025

3 In which pair is the bond angle in the first species smaller than the smallest bond angle in the second species? A CH4 and SF6 B CO2 and BF3 C H2O and H3O+ D NH4 + and NH3

1 marks

Answer: C

This question in 9701/14 May/June 2025

11 Which statement about the molecule PF5 is correct? A Every F–P–F bond angle is 90. B The central atom in the molecule does not have a lone pair of electrons. C The molecule has an overall dipole moment. D The shape of the molecule is octahedral.

1 marks

Answer: B

This question in 9701/14 May/June 2025

25 Which statement about an ammonium ion is correct? A All of the H–N–H bond angles in the ion are 90. B All of the H–N–H bond angles in the ion are 107. C The ion contains a N–H dative covalent bond which is weaker than the other three N–H covalent bonds. D The ion will react with a base as it is a weak acid.

1 marks

Answer: D

This question in 9701/14 May/June 2025

24 When dry ammonia and hydrogen chloride gases are mixed, a solid white ionic compound is formed. Two statements are listed. 1 The formation of the ionic compound is a redox reaction. 2 During the formation of the ionic compound, the H–N–H bond angle increases. Which statements are correct? A both 1 and 2 B 1 only C 2 only D neither 1 nor 2

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2025

6 Three bond angles are labelled on the molecule shown. H H H x y represents a lone H S C C N pair of electrons z H H H What is the order of decreasing size of the bond angles x, y and z? largest smallest A x y z B x z y C y z x D z y x

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2025

25 Two statements about a molecule of methanal are given. 1 It is planar. 2 It contains three  bonds. Which statements are correct? A both 1 and 2 B 1 only C 2 only D neither 1 nor 2

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2025

24 When dry ammonia and hydrogen chloride gases are mixed, a solid white ionic compound is formed. Two statements are listed. 1 The formation of the ionic compound is a redox reaction. 2 During the formation of the ionic compound, the H–N–H bond angle increases. Which statements are correct? A both 1 and 2 B 1 only C 2 only D neither 1 nor 2

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2025