Coomber's relationship
Encyclopedia
Coomber's relationship can be used to describe how the internal pressure
and dielectric constant
of a non-polar liquid
are related.
As
, which defines the internal pressure of a liquid, it can be found that:
where
is equal to the number of molecules
is the ionization potential
of the liquid
is a temperature
dependent relation based on numerical constants of the pair summation from inter-particle geometry
is the polarizability
is the volume
of the liquid
where for most non-polar liquids
Internal pressure
Internal pressure is a measure of how the internal energy of a system changes when it expands or contracts at constant temperature. It has the same dimensions as pressure, the SI unit of which is 1 pascal.Internal pressure is usually given the symbol \pi_T...
and dielectric constant
Dielectric constant
The relative permittivity of a material under given conditions reflects the extent to which it concentrates electrostatic lines of flux. In technical terms, it is the ratio of the amount of electrical energy stored in a material by an applied voltage, relative to that stored in a vacuum...
of a non-polar liquid
Liquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...
are related.
As
, which defines the internal pressure of a liquid, it can be found that:
where
is equal to the number of molecules is the ionization potentialIonization potential
The ionization energy of a chemical species, i.e. an atom or molecule, is the energy required to remove an electron from the species to a practically infinite distance. Large atoms or molecules have a low ionization energy, while small molecules tend to have higher ionization energies.The property...
of the liquid
is a temperatureTemperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
dependent relation based on numerical constants of the pair summation from inter-particle geometry
is the polarizabilityPolarizability
Polarizability is the measure of the change in a molecule's electron distribution in response to an applied electric field, which can also be induced by electric interactions with solvents or ionic reagents. It is a property of matter...
is the volumeVolume
Volume is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance or shape occupies or contains....
of the liquid
where for most non-polar liquids