Aballoon filled with 1.0 mol of argon is placed into a large chamber filled with air at 300 k and 1.0 atm. first, a vacuum pump attached to the chamber reduces the pressure to 0.1 atm. the vacuum pump is turned off, and the chamber is sealed. second, the chamber is heated to 400 k (the gas inside the chamber remains in thermodynamic equilibrium with the chamber walls). cp, m (ar)=20.79 j mol-1 k-1 calculate for this combined process, where the system is defined as the gas inside the balloon, which behaves as a perfect gas under these pressure conditions. (hint: choose any path you want; e. g. the second step could be broken down into heating from 300 to 400 k followed by irreversible isothermal expansion from 0.1 atm to the final pressure.)