The final properties at p,=0. 1 MPa are h2=2135kJ/kg,v2=1.5m3/k The change in internal energy amounts to △=h2-h-(P22-P)=2135-340(0.1×10×1.58×10°×045 1000 000 The expansion work is equal to =-△a=1055kJ/kg Chapter 7 Atmospheric Air 7.1 Atmospheric Air and state Properties 7. 1. 1 Definition of Atmospheric air(Moist air) Air is a mixture of nitrogen, oxygen, and small amounts of some other gases. Air in the atmosphere107 The final properties at 2 p = 0.1 MPa are 2 h = 2 135 kJ/kg ; 3 2 v = 1.5 m /kg The change in internal energy amounts to 6 6 2 1 2 2 1 1 0.1 10 1.5 8 10 0.045 ( ) 2 135 3 400 ( ) 1000 1000 -1 055 kJ/kg u h h p v p v      = − − − = − − − = The expansion work is equal to w u = − =1 055 kJ/kg Chapter 7 Atmospheric Air 7.1 Atmospheric Air and State Properties 7.1.1 Definition of Atmospheric air (Moist air) Air is a mixture of nitrogen, oxygen, and small amounts of some other gases. Air in the atmosphere