Liquids - Vapor Pressures
Vapor and saturation pressure for some common liquids.
The vapor pressure of a liquid is defined as the pressure exerted by the molecules that escapes from the liquid to form a separate vapor phase above the liquid surface.
The pressure exerted by the vapor phase is called the
- vapor or saturation pressure
Vapor or saturation pressure depends on temperature.
If a fluid consist of more than one component (a solution), components with
- higher vapor pressure are called light components
- lower vapor pressure are called heavy components
Temperature and Vapor or Saturation Pressure for some common Fluids
At atmospheric pressure saturation temperature of
- water : 100 oC (212 oF)
- ethyl alcohol : 78.5 oC (173 oF)
Liquids - Vapor Pressure
Approximate vapor pressure for temperatures in the range 20 oC - 25 oC (68 oF - 77 oF).
| Fluid Name | Vapor Pressure (kPa) |
|---|---|
| Acetaldehyde | 120 |
| Acetic acid | 2.1 |
| Acetic acid anhydride | 0.68 |
| Acetone | 30 |
| Allyl alcohol | 2.3 |
| Allyl chloride | 40 |
| Aluminum nitrate, 10% solution in water | 2.4 |
| Aluminum sulphate, 10% solution in water | 2.4 |
| Amyl acetate | 0.47 |
| Aniline | 0.09 |
| Beer | 2.4 |
| Benzene | 14 |
| Benzyl alcohol | 0.013 |
| Bromine | 28 |
| Butyl acetate | 1.5 |
| Butyl alcohol, 1-butanol | 0.93 |
| Butyric acid n | 0.43 |
| Calcium chloride, 25% solution in water | 2.4 |
| Calcium chloride, 5% solution in water | 2.4 |
| Carbon disulphide | 48 |
| Carbon tetrachloride | 15.3 |
| Chloroform | 26 |
| Cyclohexanol | 0.9 |
| Cyclohexanone | 0.67 |
| Ethyl acetate | 14 |
| Ethyl alcohol | 12.4 |
| Ethyl glycol | 0.7 |
| Ethylene glycol | 0.007 |
| Formic acid | 5.7 |
| Furfurol, 2-Furaldehyde | 0.3 |
| Heptane | 6 |
| Hexane | 17.6 |
| Isopropyl alcohol (rubbing alcohol) | 4.4 |
| Kerosene | 0.7 |
| Methyl acetate | 28.8 |
| Methyl alcohol, methanol | 16.9 |
| Methylene chloride, dichloromethane | 58 |
| Milk | 2.4 |
| Nitrobenzene | 0.03 |
| Nonane | 0.6 |
| Octane | 1.9 |
| Pentane | 58 |
| Phenol | 0.05 |
| Propanol | 2.8 |
| Propionic acid | 0.47 |
| Sea water | 2.4 |
| Sodium chloride, 25% solution in water | 2.4 |
| Sodium hydroxide, 20% solution in water | 2.4 |
| Sodium hydroxide, 30% solution in water | 2.4 |
| Styrene | 0.85 |
| Tetrachloroethane | 0.7 |
| Tetrachloroethylene | 2.5 |
| Toluene | 3.8 |
| Trichloroethylene | 9.2 |
| Water | 2.4 |
- 1 kPa = 103 Pa = 0.145 psi
