Schulze–Hardy rule
The generalization that the critical @C01117@ concentration for a typical @L03655@ is extremely sensitive to the @V06588@ of the @C01371@ (high @V06588@ gives a low critical @A00182@ concentration).
PAC, 1972, 31, 577. (Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry) on page 610 [Terms] [Paper]