One mole of an ideal gas, Cp = (7/2)R and Cy = (5/2)R, is compressed adiabatically in a piston/cylinder device from 2 bar and 25°C to 7 bar. The process is irreversible and requires 35% more work than...

Reference Book:
Introduction to Chemical Engineering Thermodynamics by Smith, Van Ness, etc. 7th or 8th Ed.

Extracted text: One mole of an ideal gas, Cp = (7/2)R and Cy = (5/2)R, is compressed adiabatically in a piston/cylinder device from 2 bar and 25°C to 7 bar. The process is irreversible and requires 35% more work than a reversible, adiabatic compression from the same initial state to the same final pressure. What is the entropy change of the gas?