Four moles of an ideal gas undergo a reversible isothermal expansion from volume V1 to volume V2 = 5V1 at temperature T = 400K.
a) Find the work done by the gas.
b) Find the entropy change of the gas. (J/deg)
c) If the expansion is reversible and adiabatic instead of isothermal, what is the entropy change of the gas? (J/deg)