Ionization and Dielectric Constants in Solutions
In a vacuum, the force a charge feels from another charge or electric field will not be disrupted by any “outside” forces.
However, in a medium the force between two charges will be disrupted by the medium. The extent to which it is disrupted is known as the “dielectric constant (K). This is the ratio of the force in a vacuum to the force in a medium. Fv/Fm = K.
When the solution is strongly polar (like H20), the molecules will reorient themselves to that the net electric field within the medium becomes weaker. They disrupt the external electric field. We can throw the dielectric constant into Coulomb’s Law: F = kq1q2/Kr^2. As the dielectric constant increases, the force decreases. Another way to look at this is as the constant increases, the more polarized the medium is.
Finally, if a gas is somehow ionized (loses an electron/becomes more positive), the less polar it will become. To give an example, if the Oxygen molecule in H2O loses an electron, it becomes less electronegative and the overall negative charge/polar nature of the molecule will decrease. If this decreases, K will decrease causing a larger force.
P.S. - Solid water has a lower K than liquid water
