An adiabatic piston-cylinder device initially contains 1L of air at 10 atm and 25°C. Consider the expansion of air to a final pressure of 1 atm using two different paths. Path 1: reversible expansion. Path 2: isobaric expansion (the gas is expanded from Vi to Vf at a constant pressure). Assume Cvm= 3/2R for air.
a) Knowing that air contains 21% O2 and 79% N2 by volume, calculate the initial partial pressures of O2 and N2.
b) Does the relation T2/T1 = (V2/V1)-(R/Cv,m) apply to path 2?
c) Calculate the final temperature and work for path 1.
d) Calculate the final temperature and work for path 2.