Leongw,
Assuming the initial temperature is -320F and pressure is atmospheric (14.69 psia), it will just remain a liquid until the critical temperature is reached due to heat transfer in the vessel. Then once you reach the critical temperature and stay above the critical pressure, it will be...
Elham2590,
I suggest you start with performing an energy balance around the compressor (open system, no heat transfer to the system). Forget PV and T. I really wish I never learned it or ideal gases. Complete waste!!! Think in terms of entropy, enthalpy, internal energy, pressure and...