Engineering Board Exam Reviewer · Thermodynamics · hard
When 1 kg of saturated liquid water at 100 °C and 101.325 kPa is vaporized, h fg = 2257 kJ/kg and the boundary work is about 169.4 kJ. What is the change in internal energy (u fg)?
- 2426.4 kJ
- 2257.0 kJ
- 2087.6 kJ
- 169.4 kJ
Answer
C. 2087.6 kJ
Solution
u fg = h fg - P v fg = 2257 - 169.4 = 2087.6 kJ.
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