HW 2 Properties of Pure Substance (31 pts)
1. Explain following terms (3 pts):
a) Compressed liquid
b) Saturated liquid
c) Saturated vapor
d) Saturated liquid-vapor mixture
e) Superheated vapor
2. Water at 27ºC can exist in different phases dependent upon the pressure. Give the approximate
pressure range in kPa for water being in each one of the three phases: vapor, liquid and solid (3
pts)
3. Dry ice is the name of solid carbon dioxide. How cold must it be at atmospheric (100kPa)
pressure to be solid? If it is heated at 100kPa what eventually happens? (just give approximate
numbers based on figure below) (2 pts)
4. A closed vessel contains 0.067m3 of saturated liquid and 0.933m3 of saturated vapor in
equilibrium. The mass fraction of gas is 30% and 𝑣𝑓 = 0.001043 𝑚3 /𝑘𝑔. Determine the
specific volume for saturated vapor 𝑣𝑔 (5 pts)
5. Using the figure and table given below, determine the phase(s) of water at (18 pts)
Known information:
Specific volume v = 1/ρ (ρ: density)
Density of water and ice at 0 ºC, 100kPa: 999.85kg/m3 and 916.8kg/m3
Density of water at triple point: 999.79kg/m3
a) T=180ºC, v=1m3/kg
b) T= 200ºC, P=400kPa
c) T= 230ºC, P=2.8MPa
d) T= -100 ºC
e) T= 170ºC, P=800kPa
f) P=200kPa, v=0.192m3/kg
g) P=100kPa, v=0.001088m3/kg T<50ºC
h) P=611.657 Pa (Solid/Liquid/Vapor triple point pressure), v=0.00128m3/kg