- #1
psilocybin
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Hi, most of my thermodynamics class we have been looking up enthalpy on tables when the pressure and temperature is provided. For some homework questions, the values are not on the tables, but fall in between them. What is the correct approach to finding these when the quality is not provided? For example:
Which has the capability to produce the most work in
a closed system—1 kg of steam at 800 kPa and 180°C or 1 kg
of R-134a at 800 kPa and 180°C? Take T 0 = 25°C and PQ =
100 kPa. Answers-. 623 kJ, 5.0 kj
u = 2594 . 7 kJ/kg
P = 800 kPa
v = 0 . 24720 m /kg
T = 180 ° C
s = 6 . 7155 kJ/kg ⋅ K
u 0 ≅ u f @ 25 ° C = 104 . 83 kJ/kg
v 0 ≅ v f @ 25 ° C = 0 . 001003 m /kg
P 0 = 100 kPa
s 0 ≅ s f @ 25 ° C = 0 . 3672 kJ/kg ⋅ K
T 0 = 25 ° C
(Edited in correct values)
What is the correct approach to get here?
The textbook I am using is Thermodynamics 7e (cengal)
Thanks!
Which has the capability to produce the most work in
a closed system—1 kg of steam at 800 kPa and 180°C or 1 kg
of R-134a at 800 kPa and 180°C? Take T 0 = 25°C and PQ =
100 kPa. Answers-. 623 kJ, 5.0 kj
u = 2594 . 7 kJ/kg
P = 800 kPa
v = 0 . 24720 m /kg
T = 180 ° C
s = 6 . 7155 kJ/kg ⋅ K
u 0 ≅ u f @ 25 ° C = 104 . 83 kJ/kg
v 0 ≅ v f @ 25 ° C = 0 . 001003 m /kg
P 0 = 100 kPa
s 0 ≅ s f @ 25 ° C = 0 . 3672 kJ/kg ⋅ K
T 0 = 25 ° C
(Edited in correct values)
What is the correct approach to get here?
The textbook I am using is Thermodynamics 7e (cengal)
Thanks!