degree of ionization

The phrase degree of ionization is a collective measure indicating the ionization of a group of atoms/molecules, e.g., referring to a gas or plasma. Some terms:

• fully ionized - all the molecules in a gas are ionized.
• partially ionized - some fraction are ionized.
• weakly ionized - a small fraction are ionized.

The phrase degree of ionization is also used within chemistry as a synonym for the chemistry term, degree of dissociation, a measure used for weak acids that is related to its pH, consisting of the fraction of a material's molecules that are ionized when the material is dissolved in water.