Consider a composite entity consisting of a system [= 1.2028 moles of Ar(g) – CV,m = 3/2 R]
and its surroundings [= ice/water bath containing 1.000 kg H2O(L) & H2O(s) at a constant
pressure of 1.000 atm]. The ice/water bath maintains the total entity at a constant
temperature by supplying heat to the system (or absorbing heat from the system) as needed.
The system+surroundings is adiabatic; that is, heat is exchanged only between the gas and
the ice/water bath. Initially, the gas exerts a pressure of 2.732 bar; the gas then expands to a
final pressure of 1.366 bar against a constant external, opposing pressure of 1.200 bar.
1. Calculate q for the system.
2. Do the calculations necessary to demonstrate that this process requires that 3.60
g of liquid water must freeze in the ice/water bath to account for your answer to #1.
3. Calculate ΔS for the system for this process.
4. Calculate ΔSTotal = ΔSsystem + ΔSsurroundings for this process.