Question

2.45 Hydrogen is compressed in a cylinder from 101 kPa and 15°C to 5.5 MPa and 121°C. Deter- mine Av, Au, Ah, and As for the process.

Answer 1

ALL ARE FOUND PER UNIT MASS.

volume For Hydrogen Re 8-314 we know Ideal gos equation. E212.0785 KT [kgK PV=MRT Ti = 15°C > P Q = RTI Ju= > 0, 249.0785X(157273) Pi = loi kPa = specific -245=924 mol kg = 11.854_miling Sportlerly V2 = RT2 T1 = 121°C = 182.0785X11214273) 1 Pc=5.5 MPa 55X103 L =55x60 kPa = 0.148982 m3/kg = 0-2478 miling hence oue=Ve-V7:6.1489 -5.927) X2 =-3455778 mil kg =-11-556 min ou= change in interahal energe Cou= mcr (T2-77) in = 10-31X(122-18) am= = 1042.86 KT /kg p=16.46T /19. the change in ppeaine entholou (cv = 10.31 kJ Ilok p (72-T7) y Of He } = 14.44 127-15) = 1526.4KT I kg As = change in specihc entropy = epin I _ Rin Pa = 146x (1214273) - 2.0785 x2 xin (5.580) = 4.513 – 4.1586X3.99 =-12.0825 kJ look DIV> unit mas' RT (15+273)

HENCE ALL ARE SPECIFIC QUANTITIES.

OF INTERNAL ENERGY, ENTHALPY AND ENTROPY, I HAVE USED DIRECT FORMULAE WHICH ARE ALREADY DERIVED FOR DIFFERENT PROCESS.

THANK YOU