Engineering Board Exam Reviewer · Thermodynamics · medium
Air at 101.325 kPa and 25 °C has a relative humidity of 60%. If the saturation pressure at 25 °C is 3.169 kPa, what is the partial pressure of the dry air?
- 1.901 kPa
- 99.424 kPa
- 60.795 kPa
- 98.156 kPa
Answer
B. 99.424 kPa
Solution
Pv = Pg = 0.6(3.169) = 1.901 kPa. Pa = P - Pv = 101.325 - 1.901 = 99.424 kPa.
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