Hanoi – Amsterdam High school for the gifted
Cambridge AS and A level Chemistry
Exercices – Chapter 5 – States of matter
I. MULTIPLE CHOICE QUESTIONS
Use of the Data Booklet is relevant to these questions.
1. 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 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. 1.07kPa
B. 2.14 kPa
C. 10.8 kPa
D. 21.6 kPa
2. The gas laws can be summarised in the ideal gas equation: 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?
0.00018 g
0.0032g
0.18 g
3.2 g
3. The gas laws can be summarised in the ideal gas equation: pV = nRT. 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
4. When 0.15 g of an organic compound is vaporized, 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?
5. 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
Hanoi – Amsterdam High school for the gifted
Cambridge AS and A level Chemistry
Exercices – Chapter 5 – States of matter
6. Which diagram shows the correct graph of pV against n for an ideal gas at constant
temperature?
7. 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
8. 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
9. 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
10. Which diagram correctly describes the behaviour of a fixed mass of an ideal gas?
(T is measured in K.)
Hanoi – Amsterdam High school for the gifted
Cambridge AS and A level Chemistry
Exercices – Chapter 5 – States of matter
II. STRUCTURED QUESTIONS
1. The relationship pV = nRT can be derived from the laws of mechanics by
assuming ideal behaviour for gases.
(a) The graph represents the relationship between pV and p for a real gas at three
different temperatures, T1, T2 and T3.
(i) Draw one line on the graph to show what the relationship should be for the same
amount of an ideal gas.
(ii) State and explain, with reference to the graph, which of T1, T2 or T3 is the
lowest temperature.
(iii) Explain your answer to (ii) with reference to intermolecular forces.
(iv) State and explain the effect of pressure on the extent to which a gas deviates
from ideal behaviour.
(b) A flask with a volume of 100 cm3 was first weighed with air filling the flask, and
then with another gas, Y, filling the fl ask. The results, measured at 26°C and
1.00 × 105 Pa, are shown.
Mass of fl ask containing air = 47.930 g. Mass of fl ask containing Y = 47.989 g
Density of air = 0.00118 g cm–3. Calculate the relative molecular mass, Mr, of Y.
(c) A mixture of neon and argon has a mass of 0.275 g. The mixture was placed in
a gas syringe at a temperature of 25 °C and a pressure of 100 kPa. Under these
conditions the mixture was found to occupy a volume of 200 cm3.
(i) Calculate the average Mr of the mixture.
Hanoi – Amsterdam High school for the gifted
Cambridge AS and A level Chemistry
Exercices – Chapter 5 – States of matter
(ii) Use your answer to (i) to calculate the percentage of neon in the mixture. Give
your answer to three significant figures.
2. Structure and bonding can be used to explain many of the properties of substances.
(a) Copper, ice, silicon(IV) oxide, iodine and sodium chloride are all crystalline solids.
Complete the table with:
• the name of a type of bonding found in each crystalline solid,
• the type of lattice structure for each crystalline solid.
crystalline solid
type of bonding
type of lattice structure
copper
ice
silicon(IV) oxide
iodine
sodium chloride
(b) (i) Name the strongest type of intermolecular force in ice.
(ii) Draw a fully labelled diagram of two water molecules in ice, showing the force
in (i) and how it forms.
(c) The graph represents how the temperature of a sample of copper (melting point
1085 °C) changes as it is gradually cooled from 1200 °C.
(i) Identify the state(s) of matter present during each stage of the process shown in
the graph.
(ii) State what is happening to the energy and movement of the particles in the copper
during stage X.
(iii) Explain why the temperature stays constant at T1 during stage Y.
Hanoi – Amsterdam High school for the gifted
Cambridge AS and A level Chemistry
Exercices – Chapter 5 – States of matter