Polarization in chemistry refers to the partial or complete separation of the positive and negative electric charges in a nuclear, atomic, molecular, or chemical system. It is a term used to describe the distortion of the electron density of ionic bonds to occupy the region between two nuclei. Polarization and electron distortion are directly proportional. Polarizability is the ease with which the electron cloud of an atom can be distorted to become asymmetric/Physical_Properties_of_Matter/Atomic_and_Molecular_Properties/Polarizability). The greater the number of electrons an atom has, the farther the outer electrons will be from the nucleus, and the greater the chance for them to shift positions within the molecule/Physical_Properties_of_Matter/Atomic_and_Molecular_Properties/Polarizability). Polarization is favored by the following factors/Physical_Properties_of_Matter/Atomic_and_Molecular_Properties/Polarizability):

• Small cation: the high polarizing power stems from the greater concentration of positive charge on a small area.
• Large anion: the high polarizability stems from the larger size where the outer electrons are more loosely held and can be more easily distorted by the cation.

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 mechanical side-effects include activation polarization, concentration polarization, and ohmic polarization). Undesirable polarization can be suppressed by vigorous agitation of the electrolyte).