Physics 9702 · AS & A Level
Kinetic theory of gases
50 practice questions on Kinetic theory of gases, with worked solutions and instant marking.
State what the term internal energy means.
Feb/March 2016
The pressure $p$ for an ideal gas with density $\rho$ is expressed by $p = \frac{1}{3}\rho\langle c^{2} \rangle$.
Feb/March 2019
A vessel with a volume of $85\,\text{m}^3$ contains $110\,\text{kg}$ of an ideal gas. At temperature $T$, the gas pressure is $1.0 \times 10^{5}\,\text{Pa}$. The mass of $1.0\,\text{mol}$ of this gas is $32\,\text{g}$.
Feb/March 2020
An ideal gas with a fixed mass is held at a temperature of $21\,^{\circ}\text{C}$. Its pressure is $2.3 \times 10^5\,\text{Pa}$ and its volume is $3.5 \times 10^{-3}\,\text{m}^3$.
Feb/March 2021
Cuboids P and Q, both made of metal, are in thermal contact with one another.
Feb/March 2025
A gas begins at a temperature of $27.2^\circ\text{C}$ and is then heated until it reaches $38.8^\circ\text{C}$. Calculate, in kelvin, to a suitable number of decimal places,
May/June 2010
The kinetic theory of gases rests on several simplifying assumptions. Gas molecules are treated as identical hard elastic spheres.
May/June 2012
The kinetic theory of gases is built on a number of simplifying assumptions. Gas molecules are treated as hard, elastic, identical spheres.
May/June 2012
Explain what the Avogadro constant means.
May/June 2014
What does the Avogadro constant mean?
May/June 2014
At room temperature, a gas sample contains five atoms with speeds: $1.32 \times 10^3\,\text{m s}^{-1}$, $1.50 \times 10^3\,\text{m s}^{-1}$, $1.46 \times 10^3\,\text{m s}^{-1}$, $1.28 \times 10^3\,\text{m s}^{-1}$, $1.64 \times 10^3\,\text{m s}^{-1}$. For these five atoms, calculate, to three significant figures,
May/June 2015
An ideal gas is taken to be made up of atoms or molecules that behave like hard, identical spheres, are in continual motion, and undergo elastic collisions. State two further assumptions of the kinetic theory of gases.
May/June 2016
An ideal gas is taken to be made of atoms or molecules that act as hard, identical spheres, move continuously, and experience elastic collisions. State two more assumptions of the kinetic theory of gases.
May/June 2016
Describe how molecules move in a gas, according to the kinetic theory of gases.
May/June 2017
For an ideal gas, the pressure $p$ and volume $V$ are linked to the gas density $\rho$ by $p = \frac{1}{3}\rho\langle c^2 \rangle$.
May/June 2017
Describe, in terms of the kinetic theory of gases, how molecules move in a gas.
May/June 2017
Use one assumption of the kinetic theory of gases to explain why the molecules of an ideal gas have zero potential energy.
May/June 2018
A cube-shaped box of volume $V$ holds $N$ molecules of an ideal gas. Each molecule has mass $m$.
May/June 2020
An ideal gas is held in a cylinder by a movable frictionless piston, as shown in Fig. 2.1. At first, the gas has a volume of $1.8 \times 10^{-3}\,\text{m}^3$ at a pressure of $3.3 \times 10^{5}\,\text{Pa}$ and a temperature of $310\,\text{K}$.
May/June 2021
State two basic assumptions of the kinetic theory of gases.
May/June 2023
State what the term ideal gas means.
May/June 2023
State two basic assumptions of the kinetic theory of gases.
May/June 2023
State the meaning of an ideal gas.
May/June 2024
In terms of thermal energy, what does it mean for two objects to be in thermal equilibrium?
May/June 2024
State what the term ideal gas means.
May/June 2024
An ideal gas may be described by the equation of state $pVA = NBT$, in which $p$ denotes the gas pressure, $V$ its volume, $A$ the Avogadro constant, $B$ another constant, and $N$ the number of molecules in the gas.
May/June 2025
State the meaning of an ideal gas.
May/June 2025
State the fundamental assumptions of the kinetic theory of gases.
Oct/Nov 2010
One assumption in the kinetic theory of gases is that gas molecules act like hard, elastic identical spheres. State two further assumptions of the kinetic theory of gases.
Oct/Nov 2011
One assumption of the kinetic theory of gases is that gas molecules act like hard, elastic identical spheres. State two further assumptions of the kinetic theory of gases.
Oct/Nov 2011
An ideal gas has volume $V$ and pressure $p$. For this gas, the product $pV$ is described by $pV = \frac{1}{3}Nm\langle c^2 \rangle$, where $m$ denotes the mass of one molecule of the gas.
Oct/Nov 2012
The product of the pressure $p$ and the volume $V$ for an ideal gas is given by $pV = \frac{1}{3}Nm\langle c^2 \rangle$, where $m$ is the mass of one molecule of the gas.
Oct/Nov 2013
The pressure $p$ multiplied by the volume $V$ of an ideal gas is described by $pV = \frac{1}{3}Nm\langle c^{2} \rangle$, where $m$ is the mass of a single molecule of the gas.
Oct/Nov 2013
State the meaning of the term ideal gas.
Oct/Nov 2015
State the meaning of an ideal gas.
Oct/Nov 2015
An ideal gas is taken to contain molecules that are hard elastic identical spheres. State two more assumptions of the kinetic theory of gases.
Oct/Nov 2015
State the meaning of the term ideal gas.
Oct/Nov 2018
The kinetic theory of gases rests on several assumptions about gas molecules. State the assumption that concerns the volume of the molecules of the gas.
Oct/Nov 2019
Smoke particles are kept suspended in stationary air. Brownian motion of the smoke particles is observed with a microscope.
Oct/Nov 2019
The kinetic theory of gases rests on several assumptions about gas molecules. State the assumption linked to the molecules' volume.
Oct/Nov 2019
Define the meaning of specific heat capacity.
Oct/Nov 2021
A basic assumption in the kinetic theory of gases is that every collision between gas molecules is elastic.
Oct/Nov 2021
Define the term specific heat capacity.
Oct/Nov 2021
The ideal-gas equation of state may be written as $pV = NkT$. State the meaning of each symbol in this equation: $p$, $V$, $N$, $k$, $T$.
Oct/Nov 2022
For an ideal gas, the product $pV$ is given by $pV = \frac{1}{3}Nm\langle c^2 \rangle$, where $p$ denotes the gas pressure and $V$ denotes the gas volume.
Oct/Nov 2023
For an ideal gas, the product $pV$ is given by $pV = \frac{1}{3}Nm\langle c^2 \rangle$, where $p$ is the pressure of the gas and $V$ is the volume of the gas. State what the symbols $N$, $m$ and $\langle c^2 \rangle$ mean in this equation.
Oct/Nov 2023
State the meaning of the Avogadro constant.
Oct/Nov 2024
State three of the standard assumptions used in the kinetic theory of gases.
Oct/Nov 2024
State what the Avogadro constant means.
Oct/Nov 2024
Hydrogen gas is made up of molecules, and each molecule has a mass of $3.34 \times 10^{-27}\,\text{kg}$. Hydrogen can be treated as an ideal gas. A spherical balloon holds $0.0160\,\text{mol}$ of hydrogen gas at a temperature of $282\,\text{K}$. At this temperature, the gas volume in the balloon is $1.87 \times 10^{-4}\,\text{m}^{3}$.
Oct/Nov 2025