Donnan equilibrium

 
Pronunciation: /ˈdɒn(ə)n/

noun

[mass noun] Chemistry
  • the equilibrium reached between two ionic solutions separated by a semipermeable membrane when one or more of the kinds of ion present cannot pass through the membrane. The result is a difference in osmotic pressure and electrical potential between the solutions.

Origin:

early 20th century: named after Frederick G. Donnan (1870–1956), British physical chemist