Search results
Results from the WOW.Com Content Network
In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar bonds due to a difference in electronegativity between the bonded atoms.
In organic chemistry, the term stereoelectronic effect is also used to emphasize the relation between the electronic structure and the geometry (stereochemistry) of a molecule. The term polar effect is sometimes used to refer to electronic effects, but also may have the more narrow definition of effects resulting from non-conjugated substituents.
In electrochemistry, polarization is a collective term for certain mechanical side-effects (of an electrochemical process) by which isolating barriers develop at the interface between electrode and electrolyte. These side-effects influence the reaction mechanisms, as well as the chemical kinetics of corrosion and metal deposition.
Polarization (antenna), the state of polarization (in the above sense) of electromagnetic waves transmitted by or received by a radio antenna; Dielectric polarization, charge separation in insulating materials: Polarization density, volume dielectric polarization; Dipolar polarization, orientation of permanent dipoles
The polarization is proportional to the macroscopic field by = = where is the electric permittivity constant and is the electric susceptibility. Using this proportionality, we find the local field as F = 1 3 ( ε r + 2 ) E {\displaystyle \mathbf {F} ={\tfrac {1}{3}}(\varepsilon _{\mathrm {r} }+2)\mathbf {E} } which can be used in the definition ...
Generally, the cause of concentration polarization is the ability of a membrane to transport some species more readily than the other(s) (which is the membrane permselectivity): the retained species are concentrated at the upstream membrane surface while the concentration of transported species decreases. Thus, concentration polarization ...
The polarization of a molecule through its bonds is a separate phenomenon known as induction. [3] Field effects are relatively weak, and diminish rapidly with distance, but have still been found to alter molecular properties such as acidity. [1] Field effect on a carbonyl arising from the dipole in a C-F bond.
Definition and higher orders [ edit ] The linear electric polarizability α {\displaystyle \alpha } in isotropic media is defined as the ratio of the induced dipole moment p {\displaystyle \mathbf {p} } of an atom to the electric field E {\displaystyle \mathbf {E} } that produces this dipole moment.