Dispersing Medium
Definition and meaning of Dispersing Medium in chemistry.
Dispersing medium is the continuous phase of a colloid or other dispersion, the substance in which the dispersed phase particles are distributed throughout.
In more detail
In any colloidal system, two components are present: the dispersed phase (finely divided particles, typically 1 nm to 1000 nm in size) and the dispersing medium, which surrounds and separates those particles. The dispersing medium can be a gas, liquid, or solid, and its physical state combined with that of the dispersed phase defines the type of colloid (e.g., sol, emulsion, foam, aerosol). The nature of the dispersing medium strongly influences properties such as viscosity, stability, and the Tyndall effect shown by the system.
Key facts
| Field | Physical Chemistry |
|---|---|
| Also called | Continuous phase; dispersion medium |
| Possible states | Solid, liquid, or gas |
| Counterpart | Dispersed phase (the distributed particles) |
In milk, an oil-in-water emulsion, tiny fat droplets form the dispersed phase while water acts as the dispersing medium.
Frequently asked questions
Is the dispersing medium the same as the solvent?
Not exactly. In a true solution, the dissolved solute is molecularly mixed with the solvent, whereas in a colloid the dispersing medium surrounds distinct, larger dispersed-phase particles that do not fully dissolve.
Can the dispersing medium be a gas?
Yes. In an aerosol such as fog, air is the gaseous dispersing medium and suspended water droplets are the dispersed phase.