Dissociation
The breaking apart of a solute into two or more particles when it dissolves, increasing the effective particle count.
Formula / equation
AB → A⁺ + B⁻
Unit
Dimensionless
In depth
Dissociation of an electrolyte multiplies every colligative effect by the van't Hoff factor. Strong electrolytes dissociate almost completely, while weak ones establish an equilibrium whose position, the degree of dissociation, can itself be measured from the observed colligative property.
Examples in the real world
CaCl₂ giving three ions per formula unit; acetic acid dissociating only about 1.3% in 0.1 M solution.