# physical chemistry

Based on physical chemistry

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1. One mole of an ideal monatomic gas is put through the cycle shown below:
STEP A: isochoric reduction in pressure;
STEP B: isobaric increase in volume;
STEP C: return to initial state by straight-line path (this is not isothermal).
Assuming the steps to be reversible, calculate q, w and ?U for each step and for the entire
cycle. (CV for a monotonic gas = 3R/2)
The data for the states:
STATE 1: 4.00 atm, 11.20 L, 546 K;
STATE 2: 2.00 atm, 11.20 L, 273 K;
STATE 3: 2.00 atm, 22.40 L, 546 K.
1.22, 1.24, 1.34, 1.35, 1.36, 1.37, 2.17, 2.23, 2.39, 2.43, 8.2
2. Consider the following processes:
a. Ammonium nitrate dissolves in water.
b. A tray of water freezes in the freezing compartment of an electric refrigerator.
A) Identify the macroscopic work modes (i.e., the mechanical coordinates and forces) involved in the process. Indicate what physical information is needed to calculate the amout of energy transferred through each work mode during the process.
B) Identify the pathways for thermal energy flow during the process. Identify the boundaries across which these flows occur. State the direction of each thermal energy flow.
C) Write the first law in a form appropriate for each process.
Some of these processes may be spontaneous. As defined in class, a spontaneous
process is induced by removing a constraint between system and surroundings
in the initial equilibrium state of the isolated composite. During the spontaneous
process, some properties of the system change to new values determined by the
balance of driving forces in the final equilibrium state of the isolated composite.
D) For each spontaneous process on the list, identify the constraint that is removed, and
identify the driving forces that become balanced at the end of the process. Identify those properties that come to final equilibrium values as a result of the
balance in driving forces. Briefly describe your reasoning.
E) Some of the processes on the list may not be spontaneous….