Sol
Definition and meaning of Sol in chemistry.
A sol is a specific type of colloidal dispersion consisting of solid discrete particles stably suspended within a continuous liquid phase without settling.
In more detail
In a true sol, the dispersed solid particles are physically small enough (typically measuring between 1 and 1000 nanometers in diameter) that they completely resist settling out by the force of gravity, being kept in constant suspension by random Brownian motion. Sols famously exhibit the Tyndall effect, a phenomenon where a directed beam of visible light passing through the fluid is visibly scattered by the tiny suspended particles. Many sols can be intentionally transformed into rigid gels by altering the system's temperature or by carefully adding a chemical precipitating agent.
Key facts
| Field | General Chemistry |
|---|---|
| Phases | Solid dispersed in liquid |
| Property | Tyndall effect |
Liquid household paint is a very common everyday example of a sol, consisting of microscopic solid pigment particles uniformly dispersed in a liquid carrying medium.
Frequently asked questions
What is the primary physical difference between a chemical sol and a gel?
A sol is a liquid suspension of free-moving solid particles, whereas a gel is a semi-solid material where the solid particles form a continuous interconnected network that entirely traps the liquid phase.