A 35 ft3 rigid tank has propane at 15 psia, 540 R and connected by a valve to another tank of 20 ft3 with propane at 40 psia, 720 R. The valve is opened and the two tanks come to a uniform state at 600 R. What is the final pressure?
Propane is an ideal gas (P << Pc) with R = 35.04 ft-lbf/lbm R
