A constant mass of an ideal gas has a volume of 
at a temperature of 
. When the gas is heated, 
of thermal energy causes it to expand to a volume of 
at 
. This is illustrated in the figure below.
Show that the initial and final pressures of the gas are equal.
The pressure of the gas is 
. For this heating of the gas,
calculate the work done by the gas,
use the first law of thermodynamics and your answer in (i) to determine the change in internal energy of the gas.
