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Vapor Pressure estimation by JAVA Applet

Draw molecule at cyan panel. How to use animation1, animation2
Change atom type or delete atom, mouse down and up at the same atom.

Cis-, Trans- compounds return average of both.
Hydrogen will be added automatically by program.

Reliable methods for estimating the vapor pressures of organic materials are of increasing importance as a tool in predicting the behavior and fate of chemicals that are introduced into the environment. When a chemical like a CFC or HFC has been spilled, for example, we must know its approximate vapor pressure in order to estimate its rate of evaporation, Ozone Depletion Potential (ODP) and Global Warming Potential(GWP). Without information of vapor pressure, we can not get ODP and GWP.

The persistence of environmental hormones, insecticides, herbicides, and similar substances that have been absorbed in the soil is also highly dependent on this chemical specific property.

Numerous equations and correlations for estimation vapor pressure are presented in the literature. In general, they require information on at least three of the following properties:
(1) the critical temperature,
Tc
(2) the critical pressure,
Pc
(3) the
heat of vaporization, dHv and/or
(4) the vapor pressure ( Pvp ) at some reference temperature

Most major estimating methods are following:

  • Riedel
  • Frost-Kalkwarf-Thodos
  • Riedel-Plank-Miller
  • Thek-Stiel
  • Lee-Kesler

Important correlating method are

Related Properties Boiling Point, Reduced Pressure Boiling Point , PVT , hydrogen bonding energy

, Critical properties and Antoine parameter