The gaseous state: ideal and real gases and pV = nRT — Paper 1 · A Level Chemistry 9701

5 Which gas is likely to deviate most from ideal gas behaviour? A HCl B He C CH4 D N2

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2005

6 Which of the following least resembles an ideal gas? A ammonia B helium C hydrogen D trichloromethane

1 marks

Answer: A

This question in 9701/11 May/June 2006

6 For an ideal gas, the plot of pV against p is a straight line. For a real gas, such a plot shows a deviation from ideal behaviour. The plots of pV against p for three real gases are shown below. The gases represented are ammonia, hydrogen and nitrogen. X Y Z pV ideal gas 0 0 p What are the identities of the gases X, Y and Z? X Y Z A ammonia nitrogen hydrogen B hydrogen nitrogen ammonia C nitrogen ammonia hydrogen D nitrogen hydrogen ammonia

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2006

31 What are assumptions of the kinetic theory of gases and hence of the ideal gas equation, PV = nRT ? 1 Molecules move without interacting with one another except for collisions. 2 Intermolecular forces are negligible. 3 Intermolecular distances are much greater than the molecular size.

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2007

33 Phosphorus pentachloride is introduced into an empty gas syringe which has a movable, tightly- fitting plunger. The gas is allowed to expand until equilibrium is reached at a temperature at which the phosphorus pentachloride partially dissociates. PCl5(g) PCl3(g) + Cl2(g) self-sealing cap for introducing gas plunger sample syringe oven Which statements are correct? 1 The equilibrium pressure inside the syringe will be greater than atmospheric pressure. 2 When the plunger is pushed in the equilibrium adjusts to produce more PCl5(g). 3 The volume of gas in the syringe at equilibrium will be greater than if no dissociation had occurred.

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2007

6 The density of ice is 1.00 g cm–3. What is the volume of steam produced when 1.00 cm3 of ice is heated to 323 °C (596 K) at a pressure of one atmosphere (101 kPa)? [1 mol of a gas occupies 24.0 dm3 at 25 °C (298 K) and one atmosphere.] A 0.267 dm3 B 1.33 dm3 C 2.67 dm3 D 48.0 dm3

1 marks

Answer: C

This question in 9701/11 May/June 2008

8 Which diagram correctly describes the behaviour of a fixed mass of an ideal gas? (T is measured in K.) A B C D constant T constant T constant T constant p p pV pV V 0 0 0 0 0 V 0 p 0 V 0 T

1 marks

Answer: D

This question in 9701/11 May/June 2008

7 Which of the following would behave most like an ideal gas at room temperature? A carbon dioxide B helium C hydrogen D nitrogen

1 marks

Answer: B

This question in 9701/11 Oct/Nov 2008

32 An ideal gas obeys the gas laws under all conditions of temperature and pressure. Which of the following are true for an ideal gas? 1 The molecules have negligible volume. 2 There are no forces of attraction between molecules. 3 The molecules have an average kinetic energy which is proportional to its absolute temperature.

1 marks

Answer: A

This question in 9701/11 May/June 2009

3 Which gas closely approaches ideal behaviour at room temperature and pressure? A ammonia B carbon dioxide C helium D oxygen

1 marks

Answer: C

This question in 9701/11 May/June 2010

9 Which mass of gas would occupy a volume of 3 dm3 at 25 °C and 1 atmosphere pressure? [1 mol of gas occupies 24 dm3 at 25 °C and 1 atmosphere pressure.] A 3.2 g O2 gas B 5.6 g N2 gas C 8.0 g SO2 gas D 11.0 g CO2 gas

1 marks

Answer: C

This question in 9701/11 May/June 2010

1 Which gas closely approaches ideal behaviour at room temperature and pressure? A ammonia B carbon dioxide C helium D oxygen

1 marks

Answer: C

This question in 9701/12 May/June 2010

1 Which gas closely approaches ideal behaviour at room temperature and pressure? A ammonia B carbon dioxide C helium D oxygen

1 marks

Answer: C

This question in 9701/13 May/June 2010

7 Flask X contains 5 dm3 of helium at 12 kPa pressure and flask Y contains 10 dm3 of neon at 6 kPa pressure. If the flasks are connected at constant temperature, what is the final pressure? A 8 kPa B 9 kPa C 10 kPa D 11 kPa

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2010

32 When a sample of a gas is compressed at constant temperature from 1500 kPa to 6000 kPa, its volume changes from 76.0 cm3 to 20.5 cm3. Which statements are possible explanations for this behaviour? 1 The gas behaves non-ideally. 2 The gas partially liquefies. 3 Gas is adsorbed on to the vessel walls.

1 marks

Answer: D

This question in 9701/12 May/June 2011

33 Which equations apply to an ideal gas? [p = pressure, V = volume, M = molar mass, ρ = density, c = concentration, R = gas constant, T = temperature] ρ RT cRT 1 p = 2 pV = MRT 3 pV = M M

1 marks

Answer: D

This question in 9701/12 May/June 2011

5 At room temperature and pressure chlorine does not behave as an ideal gas. At which temperature and pressure would the behaviour of chlorine become more ideal? pressure temperature / kPa / K A 50 200 B 50 400 C 200 200 D 200 400

1 marks

Answer: B

This question in 9701/11 Oct/Nov 2011

11 Which solid-line curve most accurately represents the distribution of molecular speeds in a gas at 500 K if the dotted-line curve represents the corresponding distribution for the same gas at 300 K? A B fraction of fraction of molecules molecules speed speed C D fraction of fraction of molecules molecules speed speed

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2011

33 Which are assumptions of the kinetic theory of gases and hence of the ideal gas equation, PV = nRT ? 1 Molecules move without interacting with one another except for collisions. 2 Intermolecular forces are negligible. 3 Intermolecular distances are much greater than the molecular size.

1 marks

This question in 9701/12 Oct/Nov 2011

4 At room temperature and pressure chlorine does not behave as an ideal gas. At which temperature and pressure would the behaviour of chlorine become more ideal? pressure temperature / kPa / K A 50 200 B 50 400 C 200 200 D 200 400

1 marks

Answer: B

This question in 9701/13 Oct/Nov 2011

6 Use of the Data Booklet is relevant to this question. The gas laws can be summarised in the ideal gas equation. pV = nRT 0.56 g of ethene gas is contained in a vessel at a pressure of 102 kPa and a temperature of 30 °C. What is the volume of the vessel? A 49 cm3 B 494 cm3 C 48 900 cm3 D 494 000 cm3

1 marks

Answer: B

This question in 9701/11 May/June 2012

8 Under which set of conditions is a gas most likely to behave ideally? temperature pressure A high high B high low C low high D low low

1 marks

Answer: B

This question in 9701/11 May/June 2012

31 The gas laws can be summarised in the ideal gas equation. pV = nRT where each symbol has its usual meaning. Which statements are correct? 1 One mole of an ideal gas occupies the same volume under the same conditions of temperature and pressure. 2 The density of an ideal gas at constant pressure is inversely proportional to the temperature, T. 3 The volume of a given mass of an ideal gas is doubled if its temperature is raised from 25 °C to 50 °C at constant pressure.

1 marks

Answer: B

This question in 9701/11 May/June 2012

6 Use of the Data Booklet is relevant to this question. The gas laws can be summarised in the ideal gas equation. pV = nRT 0.96 g of oxygen gas is contained in a glass vessel of volume 7000 cm3 at a temperature of 30 °C. What is the pressure in the vessel? A 1.1 kPa B 2.1 kPa C 10.8 kPa D 21.6 kPa

1 marks

Answer: C

This question in 9701/12 May/June 2012

7 Use of the Data Booklet is relevant to this question. The gas laws can be summarised in the ideal gas equation. pV = nRT 0.56 g of ethene gas is contained in a vessel at a pressure of 102 kPa and a temperature of 30 °C. What is the volume of the vessel? A 49 cm3 B 494 cm3 C 48 900 cm3 D 494 000 cm3

1 marks

Answer: B

This question in 9701/13 May/June 2012

8 Under which set of conditions is a gas most likely to behave ideally? temperature pressure A high high B high low C low high D low low

1 marks

Answer: B

This question in 9701/13 May/June 2012

33 The gas laws can be summarised in the ideal gas equation. pV = nRT where each symbol has its usual meaning. Which statements are correct? 1 One mole of an ideal gas occupies the same volume under the same conditions of temperature and pressure. 2 The density of an ideal gas at constant pressure is inversely proportional to the temperature, T. 3 The volume of a given mass of an ideal gas is doubled if its temperature is raised from 25 °C to 50 °C at constant pressure.

1 marks

Answer: B

This question in 9701/13 May/June 2012

6 Use of the Data Booklet is relevant to this question. The volume of a sample of ammonia is measured at a temperature of 60 °C and a pressure of 103 kPa. The volume measured is 5.37 × 10–3 m3. What is the mass of the sample of ammonia, given to two significant figures? A 0.00019 g B 0.0034 g C 0.19 g D 3.4 g

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2012

6 Use of the Data Booklet is relevant to this question. The volume of a sample of ammonia is measured at a temperature of 60 °C and a pressure of 103 kPa. The volume measured is 5.37 × 10–3 m3. What is the mass of the sample of ammonia, given to two significant figures? A 0.00019 g B 0.0034 g C 0.19 g D 3.4 g

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2012

17 Use of the Data Booklet is relevant to this question. 1.15 g of a metallic element reacts with 300 cm3 of oxygen at 298 K and 1 atm pressure, to form an oxide which contains O2– ions. What could be the identity of the metal? A calcium B magnesium C potassium D sodium

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2012

1 Which diagram shows the correct graph of V against p for a fixed mass of an ideal gas at constant temperature? A B C D V V V V 0 0 0 0 0 p 0 p 0 p 0 p

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2012

3 Use of the Data Booklet is relevant to this question. The volume of a sample of ammonia was measured at a temperature of 40 °C and a pressure of 95 kPa. The volume measured was 4.32 × 10–5 m3. What is the mass of the sample of ammonia? A 2.7 × 10–5 g B 2.1 × 10–4 g C 2.7 × 10–2 g D 2.1 × 10–1 g

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2012

9 Which would behave the least like an ideal gas at room temperature? A carbon dioxide B helium C hydrogen D nitrogen

1 marks

Answer: A

This question in 9701/11 May/June 2013

10 The general gas equation can be used to calculate the Mr value of a gas. For a sample of a gas of mass m g, which expression will give the value of Mr? mpV pVRT mRT pV A Mr = RT B Mr = C Mr = pV D Mr = mRT m

1 marks

Answer: C

This question in 9701/11 May/June 2013

7 Ethanol has a boiling point of 78 °C. At 101 kPa and 79 °C ethanol vapour does not perfectly obey the gas equation pV = nRT. What is the reason for this? A Ethanol vapour is in equilibrium with ethanol liquid at 79 °C. B There are intermolecular forces between the molecules of ethanol vapour. C The vapourisation of ethanol liquid is an endothermic process. D Vapours will not obey the gas equation perfectly at such a low pressure.

1 marks

Answer: B

This question in 9701/12 May/June 2013

6 Which least resembles an ideal gas at room temperature and pressure? A ammonia B helium C hydrogen D methane

1 marks

Answer: A

This question in 9701/13 May/June 2013

7 Use of the Data Booklet is relevant to this question. When 0.15 g of an organic compound is vaporised, it occupies a volume of 65.0 cm3 at 405 K and 1.00 × 105 Nm–2. Using the expression pV = nRT, which of the following expressions should be used to calculate the relative molecular mass, Mr, of the compound? 0 . 15 × 65 × 10 − 6 × 1 × 10 5 A 8 . 31 × 405 B 0 . 15 × 8 . 31 × 405 1 × 10 5 × 65 × 10 − 3 0 . 15 × 65 × 10 − 3 × 1 × 10 5 C 8 . 31 × 405 D 0 . 15 × 8 . 31 × 405 1 × 10 5 × 65 × 10 − 6

1 marks

Answer: D

This question in 9701/13 May/June 2013

8 Use of the Data Booklet is relevant to this question. The approximate percentage composition of the atmosphere on four different planets is given in the table below. The density of a gas may be defined as the mass of 1 dm3 of the gas measured at s.t.p. Which mixture of gases has the greatest density? major gases / planet % by number of molecules A Jupiter H2 89.8, He 10.2 B Neptune H2 80.0, He 19.0, CH4 1.0 C Saturn H2 96.3, He 3.25, CH4 0.45 D Uranus H2 82.5, He 15.2, CH4 2.3

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2013

8 Use of the Data Booklet is relevant to this question. The approximate percentage composition of the atmosphere on four different planets is given in the table below. The density of a gas may be defined as the mass of 1 dm3 of the gas measured at s.t.p. Which mixture of gases has the greatest density? major gases / planet % by number of molecules A Jupiter H2 89.8, He 10.2 B Neptune H2 80.0, He 19.0, CH4 1.0 C Saturn H2 96.3, He 3.25, CH4 0.45 D Uranus H2 82.5, He 15.2, CH4 2.3

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2013

7 Measured values of the pressure, volume and temperature of a known mass of a gaseous compound are to be substituted into the equation pV = nRT. The measurements are used to calculate the relative molecular mass, Mr, of a compound. Which conditions of pressure and temperature would give the most accurate value of Mr? pressure temperature A high high B high low C low high D low low

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2013

9 Use of the Data Booklet is relevant to this question. When an evacuated fluorescent light tube of volume 300 cm3 is filled with a gas at 300 K and 101 kPa, the mass of the tube increases by 1.02 g. The gas obeys the ideal gas equation pV = nRT. What is the identity of the gas? A argon B krypton C neon D nitrogen

1 marks

Answer: B

This question in 9701/13 Oct/Nov 2013

2 Use of the Data Booklet is relevant to this question. Iodine is a black, shiny, non-metallic solid and a member of Group VII. It sublimes easily on heating to give a purple vapour. A sample of iodine vapour of mass 6.35 g has a volume of 1.247 dm3 when maintained at constant temperature and a pressure of 1.00 × 105 Pa. If iodine vapour acts as an ideal gas, what is the temperature of the iodine vapour? A 300 K B 600 K C 300 000 K D 600 000 K

1 marks

Answer: B

This question in 9701/11 May/June 2014

7 A 10.0 cm3 bubble of an ideal gas is formed on the sea bed where it is at a pressure of 2020 kPa. Just below the sea surface the pressure is 101 kPa and the temperature is the same as the sea bed. What is the volume of the bubble when it rises to just below the sea surface? A 10.0 cm3 B 20.2 cm3 C 200 cm3 D 2 020 000 cm3

1 marks

Answer: C

This question in 9701/13 May/June 2014

4 Two glass vessels M and N are connected by a closed valve. M N M contains helium at 20 °C at a pressure of 1 × 105 Pa. N has been evacuated, and has three times the volume of M. In an experiment, the valve is opened and the temperature of the whole apparatus is raised to 100 °C. What is the final pressure in the system? A 3.18 × 104 Pa B 4.24 × 104 Pa C 1.25 × 105 Pa D 5.09 × 105 Pa

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2014

34 A student borrowed a friend’s chemistry notes and copied out the notes in the box below. Which statements are correct? A gas behaves less like an ideal gas when the gas 1 is at low pressure. 2 is at low temperature. 3 can be easily liquefied.

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2014

4 Two glass vessels M and N are connected by a closed valve. M N M contains helium at 20 °C at a pressure of 1 × 105 Pa. N has been evacuated, and has three times the volume of M. In an experiment, the valve is opened and the temperature of the whole apparatus is raised to 100 °C. What is the final pressure in the system? A 3.18 × 104 Pa B 4.24 × 104 Pa C 1.25 × 105 Pa D 5.09 × 105 Pa

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2014

34 A student borrowed a friend’s chemistry notes and copied out the notes in the box below. Which statements are correct? A gas behaves less like an ideal gas when the gas 1 is at low pressure. 2 is at low temperature. 3 can be easily liquefied.

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2014

9 Use of the Data Booklet is relevant to this question. When an evacuated glass tube of volume 200 cm3 is filled with a gas at 300 K and 101 kPa, the mass of the tube increases by 1.06 g. What is the identity of the gas? A argon B krypton C neon D xenon

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2014

5 Use of the Data Booklet is relevant to this question. The gas laws can be summarised in the ideal gas equation below. pV = nRT 0.96 g of oxygen gas is contained in a glass vessel of volume 7.0 × 10–3 m3 at a temperature of 30 °C. Assume the gas behaves as an ideal gas. What is the pressure in the vessel? A 1.1 kPa B 2.1 kPa C 10.8 kPa D 21.6 kPa

1 marks

Answer: C

This question in 9701/11 May/June 2015

5 Use of the Data Booklet is relevant to this question. The gas laws can be summarised in the ideal gas equation below. pV = nRT The volume of a sample of methane is measured at a temperature of 60 °C and a pressure of 103 kPa. The volume measured is 5.37 × 10–3 m3. Assume the gas behaves as an ideal gas. What is the mass of the sample of methane, given to two significant figures? A 0.00018 g B 0.0032 g C 0.18 g D 3.2 g

1 marks

Answer: D

This question in 9701/12 May/June 2015

4 Flask X contains 5 dm3 of helium at 12 kPa pressure and flask Y contains 10 dm3 of neon at 6 kPa pressure. If the flasks are connected at constant temperature, what is the final pressure? A 8 kPa B 9 kPa C 10 kPa D 11 kPa

1 marks

This question in 9701/12 Oct/Nov 2015

33 Which equations can apply to an ideal gas? [p = pressure, V = volume, M = molar mass, ρ = density, c = concentration, R = gas constant, T = temperature] ρ RT cRT 1 p = 2 pV = M 3 pV = MRT M

1 marks

This question in 9701/12 Oct/Nov 2015

7 What is the volume of steam produced when 1.00 g of ice is heated to 323 °C at a pressure of 101 kPa? A 0.27 dm3 B 1.3 dm3 C 2.7 dm3 D 48 dm3

1 marks

Answer: C

This question in 9701/12 Feb/March 2016

32 What are basic assumptions of the kinetic theory as applied to an ideal gas? 1 Gas particles are in continuous random motion. 2 Gas particles experience no intermolecular forces. 3 The volume of each gas particle is zero.

1 marks

Answer: A

This question in 9701/11 May/June 2016

6 Argon is a gas used to fill electric light bulbs. Under which conditions of pressure and temperature will argon behave most like an ideal gas? pressure temperature A high high B high low C low high D low low

1 marks

Answer: C

This question in 9701/12 May/June 2016

7 0.10 g of the volatile liquid X formed 0.025 dm3 of vapour at 100 °C and atmospheric pressure. 1 mol of vapour occupies 22.4 dm3 at 0 °C and atmospheric pressure. What is the relative molecular mass of X? 0.025 × 273 × 22.4 A 0.10 × 373 0 . 025 × 373 × 22 . 4 B 0 . 10 × 273 0 . 10 × 273 × 22 . 4 C 0 . 025 × 373 0 . 10 × 373 × 22 . 4 D 0 . 025 × 273

1 marks

Answer: D

This question in 9701/12 May/June 2016

2 What will make it more likely that a gas will approach ideal behaviour? A higher pressure B lower temperature C more polar molecules D weaker intermolecular forces

1 marks

Answer: D

This question in 9701/13 May/June 2016

2 In the ideal gas equation, pV = nRT, what are the units of n and T ? n T A no units °C B no units K C mol °C D mol K

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2016

7 The approximate percentage composition of the atmospheres on four different planets is given in the table below. Which mixture of gases has the greatest density? major gases / planet % by number of molecules H2 He CH4 A Jupiter 89.8 10.2 0.0 B Neptune 80.0 19.0 1.0 C Saturn 96.3 3.3 0.4 D Uranus 82.5 15.2 2.3

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2016

12 1.15 g of a metallic element needs 300 cm3 of oxygen for complete reaction, at 298 K and 1 atm pressure, to form an oxide which contains O2– ions. What could be the identity of this metallic element? A calcium B magnesium C potassium D sodium

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2016

2 In the ideal gas equation, pV = nRT, what are the units of n and T ? n T A no units °C B no units K C mol °C D mol K

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2016

7 The approximate percentage composition of the atmospheres on four different planets is given in the table below. Which mixture of gases has the greatest density? major gases / planet % by number of molecules H2 He CH4 A Jupiter 89.8 10.2 0.0 B Neptune 80.0 19.0 1.0 C Saturn 96.3 3.3 0.4 D Uranus 82.5 15.2 2.3

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2016

12 1.15 g of a metallic element needs 300 cm3 of oxygen for complete reaction, at 298 K and 1 atm pressure, to form an oxide which contains O2– ions. What could be the identity of this metallic element? A calcium B magnesium C potassium D sodium

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2016

5 At a temperature of 2500 K and a pressure of 1.00 × 10–4 Pa a sample of 0.321 g of sulfur vapour has a volume of 2.08 × 106 m3. What is the molecular formula of sulfur under these conditions? A S B S2 C S4 D S8

1 marks

Answer: A

This question in 9701/12 May/June 2017

5 All gases listed are at the same pressure. Which gas will most closely approach ideal behaviour? A ammonia at 100 K B ammonia at 500 K C neon at 100 K D neon at 500 K

1 marks

Answer: D

This question in 9701/13 May/June 2017

5 A fluorescent light tube has an internal volume of 400 cm3 and an internal pressure of 200 kPa. It is filled with 0.03 moles of an ideal gas. What is the temperature of the gas inside the fluorescent light tube? A 3.21 × 10–1 K B 3.21 × 102 K C 3.21 × 105 K D 3.21 × 108 K

1 marks

Answer: B

This question in 9701/11 Oct/Nov 2017

5 A sample of an ideal gas is contained at a constant temperature of 300 K in a gas syringe. p V The pressure is increased and a graph of RT against pressure is plotted. Which graph correctly represents the results? A B pV RT C D p

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2017

5 A fluorescent light tube has an internal volume of 400 cm3 and an internal pressure of 200 kPa. It is filled with 0.03 moles of an ideal gas. What is the temperature of the gas inside the fluorescent light tube? A 3.21 × 10–1 K B 3.21 × 102 K C 3.21 × 105 K D 3.21 × 108 K

1 marks

Answer: B

This question in 9701/13 Oct/Nov 2017

7 The gas laws can be summarised in the ideal gas equation. pV = nRT 0.960 g of oxygen gas is contained in a vessel of volume 7.00 × 10–3 m3 at a temperature of 30 °C. Assume that the gas behaves as an ideal gas. What is the pressure in the vessel? A 1.07 kPa B 2.14 kPa C 10.8 kPa D 21.6 kPa

1 marks

Answer: C

This question in 9701/12 Feb/March 2018

32 A container is partially filled with hot water, sealed and left to cool. Which statements are correct? 1 As the temperature decreases, water molecules lose kinetic energy. 2 As the temperature decreases, more water molecules move from vapour to liquid. 3 As the temperature decreases, the vapour pressure of the water decreases.

1 marks

Answer: A

This question in 9701/12 Feb/March 2018

6 Which gas is likely to deviate most from ideal gas behaviour? A HCl B He C CH4 D N2

1 marks

Answer: A

This question in 9701/12 May/June 2018

6 Which diagram correctly describes the behaviour of a fixed mass of an ideal gas? (T is measured in K.) A B C D constant p constant T constant T constant T V p pV pV 0 0 0 0 0 T 0 V 0 p 0 V

1 marks

Answer: A

This question in 9701/13 May/June 2018

36 Under room conditions, 600 cm3 of a gas, X, has a mass of 0.700 g. What could X be? 1 carbon monoxide 2 ethene 3 nitrogen

1 marks

Answer: A

This question in 9701/13 May/June 2018

2 What is a basic assumption of the kinetic theory, as applied to an ideal gas? A Collisions between gas molecules are elastic. B Each gas molecule occupies a finite volume. C Gases consist of particles that experience the force of gravity. D Gas molecules attract each other with weak intermolecular forces.

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2018

5 In this question you should assume methane behaves as an ideal gas. The gas laws can be summarised in the ideal gas equation below. pV = nRT The volume of a sample of methane is measured at a temperature of 60 °C and a pressure of 103 kPa. The volume measured is 5.37 × 10–3 m3. What is the mass of the sample of methane, given to two significant figures? A 0.0032 g B 0.018 g C 3.2 g D 18 g

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2018

5 Flask X contains 5 dm3 of helium at 12 kPa pressure and flask Y contains 10 dm3 of neon at 6 kPa pressure. If the flasks are connected at constant temperature, what is the final pressure? A 8 kPa B 9 kPa C 10 kPa D 11 kPa

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2018

2 What is a basic assumption of the kinetic theory, as applied to an ideal gas? A Collisions between gas molecules are elastic. B Each gas molecule occupies a finite volume. C Gases consist of particles that experience the force of gravity. D Gas molecules attract each other with weak intermolecular forces.

1 marks

Answer: A

This question in 9701/13 Oct/Nov 2018

5 In this question you should assume methane behaves as an ideal gas. The gas laws can be summarised in the ideal gas equation below. pV = nRT The volume of a sample of methane is measured at a temperature of 60 °C and a pressure of 103 kPa. The volume measured is 5.37 × 10–3 m3. What is the mass of the sample of methane, given to two significant figures? A 0.0032 g B 0.018 g C 3.2 g D 18 g

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2018

6 A sample of gas occupies 240 cm3 at 37 °C and 100 kPa. How many moles of gas are present in the sample? A 9.32 × 10–6 B 9.32 × 10–3 C 0.0781 D 78.1

1 marks

Answer: B

This question in 9701/12 Feb/March 2019

6 When an evacuated tube of volume 400 cm3 is filled with gas at 300 K and 101 kPa, the mass of the tube increases by 0.65 g. Assume the gas behaves as an ideal gas. What could be the identity of the gas? A argon B helium C krypton D neon

1 marks

Answer: A

This question in 9701/11 May/June 2019

7 Under which conditions will nitrogen behave most like an ideal gas? temperature pressure A low high B high low C low low D high high

1 marks

Answer: B

This question in 9701/11 May/June 2019

6 X, Y and Z are all gases that behave ideally and react according to the equation shown. X(g) + 2Y(g) → 2Z(g) When 3.0 mol of X and 3.0 mol of Y are placed inside a container with a volume of 1.0 dm3, they react to form the maximum amount of Z. The final temperature of the reaction vessel is 120 °C. What is the final pressure inside the reaction vessel? A 4.49 × 106 Pa B 9.80 × 106 Pa C 1.47 × 107 Pa D 1.96 × 107 Pa

1 marks

Answer: C

This question in 9701/12 May/June 2019

7 What changes in conditions or molecular properties make it more likely that gases approach ideal behaviour? A higher pressure B lower temperature C more polar molecules D weaker intermolecular forces

1 marks

Answer: D

This question in 9701/13 May/June 2019

5 In this question you should assume the vapour behaves as an ideal gas. 0.175 g of a volatile liquid produces a vapour of volume 4.50 × 10–5 m3 at 100 °C and pressure of 1.013 × 105 Pa. What is the Mr of the liquid? A 31.9 B 87.1 C 119 D 127

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2019

9 1.8 g of water, heated to 227 °C in a sealed container, turns to steam with a pressure of 200 kPa. What is the approximate volume of the container? A 9 × 10–4 m3 B 2 × 10–3 m3 C 2 m3 D 8 × 107 m3

1 marks

Answer: B

This question in 9701/12 Feb/March 2020

4 10 cm3 of ethane is burned in 45 cm3 of oxygen at a pressure of 101 kPa and a temperature of 200 °C. Complete combustion takes place. What is the total volume of gas present when the reaction is complete, measured under the same conditions? A 30 cm3 B 50 cm3 C 55 cm3 D 60 cm3

1 marks

Answer: D

This question in 9701/11 May/June 2020

9 A sample of argon gas has a mass of 0.20 g, at a pressure of 100 000 Pa and a temperature of 12 °C. Which volume does the gas occupy? A 1.2 × 10–4 cm3 B 5.0 cm3 C 59 cm3 D 119 cm3

1 marks

Answer: D

This question in 9701/11 May/June 2020

9 The complete combustion of 2 moles of an alkane produces 400 dm3 of carbon dioxide measured at 301 K and 1 × 105 Pa. Carbon dioxide can be assumed to behave as an ideal gas under these conditions. What is the formula of the alkane? A C8H18 B C16H34 C C20H42 D C40H82

1 marks

Answer: A

This question in 9701/12 May/June 2020

6 A graph of pV against T is shown for a fixed mass of gas. (p = pressure, V = volume and T = temperature in K.) pV T Which gas gives this graph over the widest range of temperatures and pressures? A hydrogen, H2 B hydrogen chloride, HCl C hydrogen fluoride, HF D oxygen, O2

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2020

7 A weather balloon is filled with 12.0 kg helium. The weather balloon reaches a height of 20 km, the pressure inside the balloon is 6000 Pa and the temperature is 216 K. What is the volume of the weather balloon at this height, correct to three significant figures? A 897 dm3 B 1790 dm3 C 897 000 dm3 D 1 790 000 dm3

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2020

6 A solution contains 0.25 g of sulfur dioxide in 1.00 dm3 of water. Which volume of sulfur dioxide, measured at 50 C and a pressure of 1  105 Pa, must be added to 1.00 dm3 of water to produce this solution? A 0.0162 cm3 B 0.105 cm3 C 16.2 cm3 D 105 cm3

1 marks

Answer: D

This question in 9701/12 Feb/March 2021

33 Many gases do not obey the general gas equation at high pressures. Why is this? 1 At higher pressures the molecules have more energy. 2 At higher pressures the volume of the molecules is a larger proportion of the total volume. 3 At higher pressures the molecules experience greater intermolecular forces.

1 marks

Answer: C

This question in 9701/12 Feb/March 2021

8 Which gas would behave most like an ideal gas under room conditions? A helium B nitrogen C ammonia D krypton

1 marks

Answer: A

This question in 9701/11 May/June 2021

33 A gaseous hydrocarbon has a density of 2.42 g dm–3 under room conditions. What could be the skeletal formula of this hydrocarbon? 1 2 3

1 marks

Answer: D

This question in 9701/11 May/June 2021

5 Flask Q contains 5 dm3 of helium at 12 kPa pressure. Flask R contains 10 dm3 of neon at 6 kPa pressure. If the flasks are connected at constant temperature, what is the final pressure? A 8 kPa B 9 kPa C 10 kPa D 11 kPa

1 marks

Answer: A

This question in 9701/12 May/June 2021

24 A mixture of ethanol and methanol is burned in oxygen to produce 35 cm3 of CO2 and 55 cm3 of H2O. Complete combustion occurs and the volumes of both products are measured at 101 kPa and 120 C. What is the molar ratio, ethanol : methanol, in the mixture? A 1 : 3 B 2 : 3 C 3 : 2 D 3 : 1

1 marks

Answer: D

This question in 9701/13 May/June 2021

6 Which substance shows the greatest deviation from the properties of an ideal gas under room conditions? A CO2(g) B H2(g) C Ne(g) D NH3(g)

1 marks

Answer: D

This question in 9701/11 Oct/Nov 2021

8 The general gas equation can be used to calculate the value of the Mr of a gas. For a sample of a gas of mass m grams, which expression will give the value of Mr? mRT pVRT mpV pV A Mr = pV B Mr = C Mr = RT D Mr = mRT m

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2021

6 Which substance shows the greatest deviation from the properties of an ideal gas under room conditions? A CO2(g) B H2(g) C Ne(g) D NH3(g)

1 marks

Answer: D

This question in 9701/13 Oct/Nov 2021

7 ‘Black powder’ is a mixture of potassium nitrate, carbon and sulfur. The mixture reacts as shown. 4KNO3(s) + 7C(s) + S(s)  3CO2(g) + 3CO(g) + 2N2(g) + K2S(s) + K2CO3(s) A sealed tube containing black powder has a volume of 10.0 cm3. When all of the black powder reacts, the reaction causes a pressure of 2  106 Pa and a temperature of 2500 K. The volume of the K2CO3 and K2S produced can be ignored. How many moles of KNO3 are contained in the sealed tube? A 4.81  10–4 B 9.63  10–4 C 1.93  10–3 D 9.63  10–1

1 marks

Answer: A

This question in 9701/11 May/June 2022

7 Which gas will behave least like an ideal gas at 150 C and 101 kPa? A ammonia B fluorine C krypton D steam

1 marks

Answer: D

This question in 9701/12 May/June 2022

8 When an evacuated glass bulb of volume 200 cm3 is filled with a gas at 300 K and 101 kPa, the mass of the bulb increases by 0.68 g. The gas obeys the ideal gas equation. What is the identity of the gas? A argon B krypton C neon D nitrogen

1 marks

Answer: B

This question in 9701/12 May/June 2022

8 A student reacts 1 mol of magnesium powder in a sealed 0.030 m3 container of oxygen at a pressure of 2.0  105 Pa and a temperature of 600 K. The magnesium reacts completely to form MgO. Which percentage of the oxygen will be used up? A 5.0% B 10% C 42% D 83%

1 marks

Answer: C

This question in 9701/13 May/June 2022

14 Each of the substances shown is gaseous. Which substance is most likely to show ideal behaviour in the conditions shown? temperature pressure substance / K / Pa A carbon dioxide 250 1.00  105 B hydrogen chloride 1000 1.00  106 C nitrogen 1000 1.00  105 D oxygen 250 1.00  106

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2022

15 Which graph represents the variation of pressure p and volume V of a sample of an ideal gas at constant temperature? A B p p 0 0 0 0 V V C D p p 0 0 0 0 V V

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2022

9 Under which conditions will nitrogen behave most like an ideal gas? temperature pressure A low high B high low C low low D high high

1 marks

Answer: B

This question in 9701/12 Feb/March 2023

7 Which assumptions are made about ideal gases? 1. Ideal gases contain molecules with no mass. 2 Ideal gases contain molecules with no volume. 3 Ideal gases have no intermolecular forces. A 1,2and3 B 1tand2only C 1and3only D = 2and3only

1 marks

Answer: D

This question in 9701/13 May/June 2023

8 This amount of oxygen gas has a volume of 6.00cm3 when measured at 1.00 × 105Pa and 35°C. What is the concentration of oxygen gas in the water? (You should assume that oxygen behaves as an ideal gas.) A 2.34 × 10−4moldm−3 B 1.17 × 10−3moldm−3 C 1.25 × 10−3moldm−3 D 1.03 × 10−2moldm−2

1 marks

Answer: B

This question in 9701/13 May/June 2023

7 the tube increases by 0.65g. Assume the gas behaves as an ideal gas. What is the identity of the gas? A argon B helium C krypton D neon

1 marks

Answer: A

This question in 9701/11 Oct/Nov 2023

9 At a temperature of 2500K and a pressure of 1.00 × 10–4Pa, a sample of 0.321g of sulfur vapour has a volume of 2.08 × 106m3. What is the molecular formula of sulfur under these conditions? A S B S2 C S4 D S8

1 marks

Answer: A

This question in 9701/12 Oct/Nov 2023

14 A mixture of the three gases, oxygen, nitrogen and argon, is at a total pressure of 500kPa. There is a total of 1.2 moles of gas in the mixture. If the oxygen gas alone occupied the entire volume of the mixture, it would exert a pressure of 150kPa. At room conditions the amount of nitrogen gas in the mixture would occupy a volume of 5.76dm3. What is the partial pressure of the argon gas in the mixture? A 150kPa B 200kPa C 250kPa D 300kPa 0.200mol of sulfur dioxide and 0.200mol of oxygen are placed in a 1.00dm3 sealed container. The

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2023

7 the tube increases by 0.65g. Assume the gas behaves as an ideal gas. What is the identity of the gas? A argon B helium C krypton D neon

1 marks

Answer: A

This question in 9701/13 Oct/Nov 2023

7 What is the density of a sample of fluorine gas at 32 C and 100 000 Pa? Assume fluorine behaves as an ideal gas under these conditions. A 1.4 g dm–3 B 1.5 g dm–3 C 1.6 g dm–3 D 1.7 g dm–3

1 marks

Answer: B

This question in 9701/11 May/June 2024

14 Graphs can be drawn to show the percentage of ammonia at equilibrium when nitrogen and hydrogen are mixed at different temperatures and pressures. Which diagram correctly represents these two graphs? % NH, at equilibrium 0 10 20 pressure/10°kPa Cc % NH, at equilibrium 0 10 20 pressure/10°kPa % NH, at equilibrium 0 10 20 pressure/10°kPa D % NH, at equilibrium 0 10 20 pressure/10°kPa

1 marks

Answer: D

This question in 9701/11 May/June 2024

7 In this question it should be assumed that nitrogen behaves as an ideal gas under the conditions stated. Which volume is occupied by 1.00 g of nitrogen at 50.0 C and at a pressure of 120 kPa? A 0.124 dm3 B 0.799 dm3 C 1.60 dm3 D 22.4 dm3

1 marks

Answer: B

This question in 9701/12 May/June 2024

7 The diagram shows the apparatus used to find the relative molecular mass of a volatile liquid. When 0.10 g of a volatile liquid is injected into the syringe, all of the volatile liquid evaporates and the volume increases by 85 cm3. The heater maintains a temperature of 400 K and the experiment is carried out at a pressure of 101 300 Pa. syringe volatile liquid injected here thermometer heater If the vapour of the volatile liquid behaves as an ideal gas, which expression can be used to calculate the relative molecular mass of the liquid? A Mr = (85  101 300)  (0.10  8.31  400) B Mr = (85  101.3)  (0.10  8.31  400) C Mr = (0.10  8.31  400)  (85  10–6  101 300) D Mr = (0.10  8.31  400)  (85  10–6  101.3)

1 marks

Answer: C

This question in 9701/13 May/June 2024

23 7.5 g of nitrogen monoxide reacts with 7.0 g of carbon monoxide on the surface of the catalytic converter in the exhaust system of a car. What is the total volume of the product gases measured at room conditions? A 3.0 dm3 B 6.0 dm3 C 9.0 dm3 D 12.0 dm3

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2024

7 In this question you may assume that nitrogen behaves as an ideal gas. One atmosphere pressure = 101 kPa. Which volume does 1.0 g of nitrogen occupy at 50 C and a pressure of 2.0 atmospheres? A 70 cm3 B 150 cm3 C 470 cm3 D 950 cm3

1 marks

Answer: C

This question in 9701/12 Oct/Nov 2024

23 7.5 g of nitrogen monoxide reacts with 7.0 g of carbon monoxide on the surface of the catalytic converter in the exhaust system of a car. What is the total volume of the product gases measured at room conditions? A 3.0 dm3 B 6.0 dm3 C 9.0 dm3 D 12.0 dm3

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2024

8 An excess of zinc reacts with x cm3 of 2.00 mol dm–3 hydrochloric acid. The gas produced is dried and collected. The gas occupies 1.534 dm3 at 101 000 Pa and 293 K. The gas produced behaves as an ideal gas. What is the value of x? A 31.8 cm3 B 34.7 cm3 C 63.6 cm3 D 69.4 cm3

1 marks

Answer: C

This question in 9701/12 Feb/March 2025

13 The diagram shows two containers of methane connected by a closed tap. Each container has a volume of 1.00m3. tap 16g methane at 100kPa 96g methane at 200kPa The tap is opened. The temperature of the system is changed to 800K. The system reaches constant pressure. What is the pressure of methane within the system? A 23.3kPa B 46.6kPa C 186kPa D 372kPa

1 marks

Answer: A

This question in 9701/11 May/June 2025

12 A sample of an ideal gas occupies 240 cm3 at 37 °C and 100 kPa. How many moles of gas are present in the sample? A 9.32  10–6 B 9.32  10–3 C 0.0781 D 78.1

1 marks

Answer: B

This question in 9701/12 May/June 2025

14 When 0.15g of an organic compound is vaporised, it occupies a volume of 65.0cm® at 405K and 1.00 x 10°Pa. Using the expression pV = nRT, which expression should be used to calculate the relative molecular mass, M,, of the compound? 0.15 x 65 x 10°§ x 1 x 10° A 8.31 x 405 B 0.15 x 8.31 x 405 1x 10° x 65 x 10° Cc 0.15 x 65 x 10° x 1 x 10° 8.31 x 405 D 0.15 x 8.31 x 405 1x 10° x 65 x 10°§

1 marks

Answer: D

This question in 9701/13 May/June 2025

4 Two glass vessels, M and N, are connected by a closed valve. M N M contains helium at 20 C at a pressure of 1  105 Pa. N has been evacuated, and has three times the volume of M. The valve is opened and the temperature of the whole apparatus is raised to 100 C. What is the final pressure in the system? A 3.18  104 Pa B 4.24  104 Pa C 1.25  105 Pa D 5.09  105 Pa

1 marks

Answer: A

This question in 9701/14 May/June 2025

10 A 69.0 g sample of nitrogen dioxide is placed in a reaction vessel. The initial pressure of the nitrogen dioxide is P. An effective catalyst is then added and the nitrogen dioxide begins to decompose into its elements. After ten minutes, the total pressure is 1.1P. What is the mass of oxygen molecules in the reaction vessel after ten minutes? A 4.80 g B 9.60 g C 38.4 g D 48.0 g

1 marks

Answer: B

This question in 9701/14 May/June 2025

11 1.00g of nitrogen gas is stored in a 2.00dm3 vessel at 40.0°C. What is the pressure in the vessel? A 5940Pa B 11900Pa C 46400Pa D 92900Pa

1 marks

Answer: C

This question in 9701/11 Oct/Nov 2025

8 A pure sample of a gas has a density of 2.62 g dm–3 at 101 000 Pa and 25 °C. The gas behaves ideally under these conditions. Which expression gives the Mr of the gas? 101 000  0.001 A 2.62  8.31  25 101 000  0.001 B 2.62  8.31  298 2.62  8.31  25 C 101 000  0.001 2.62  8.31  298 D 101 000  0.001

1 marks

Answer: D

This question in 9701/12 Oct/Nov 2025

11 1.00g of nitrogen gas is stored in a 2.00dm3 vessel at 40.0°C. What is the pressure in the vessel? A 5940Pa B 11900Pa C 46400Pa D 92900Pa

1 marks

Answer: C

This question in 9701/13 Oct/Nov 2025