Reversible and Irreversible Expansion/Compression Processes: Example Problems

Try to solve these problems before watching the solutions in the screencasts.

Example Problem 1

An ideal gas expands from 10 bar and 205°C to 1.5 bar and 150°C. The expansion is irreversible and adiabatic. What is the change in enthalpy for 10 mol of gas?  CP = 30 J/(mol K)

Example Problem 2

One mole of an ideal gas in a closed piston/cylinder is compressed from 300 K and 0.10 MPa to 0.8 MPa in an isothermal pathway. Calculate DU. DH, Q, and WEC if CP = 30 J/(mol K).

A third example problem can be found here that calculates the final conditions for an adiabatic compression of an ideal gas.