
The pressure
and volume
of an ideal gas are related to the density
of the gas by the expression

State what is meant by the symbol
.
Use the expression to show that the mean kinetic energy
of a gas molecule is given by

where
is the Boltzmann constant and
is the thermodynamic temperature.
An ideal gas containing
of molecules is heated at constant volume. Use the expression in (a)(ii) to show that the thermal energy required to raise the temperature of the gas by
has a value of
, where
is the molar gas constant.