The first law of thermodynamics may be represented by the equation
State what is meant by each of the following symbols.
: ...........................................................
: .............................................................................
: .............................................................................
An amount of 
of an ideal gas is held in an insulated cylinder fitted with a piston, as shown in the figure below.
Atmospheric pressure is 
. The volume of the gas is suddenly increased from 
to 
. For the expansion of the gas,
calculate the work done by the gas and hence show that the internal energy changes by 
,
determine the temperature change of the gas and state whether the change is an increase or a decrease.
