Colloids, also known as colloidal solutions or colloidal systems, are mixtures in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance. The size of the suspended particles in a colloid ranges from 1 to 1000 nanometers (10-9 meters). Colloids are classified into many types.
- Based on their physical state, colloids can be divided into solid solution, aerosol, gels, and emulsions.
- Based on their dispersion medium, colloids can be divided into hydrosol, alcosol, and acrosol.
- Based on their interaction forces, colloids can be divided into lyophobic sol and lyophilic sol.
From the classification of colloids, it can be seen that sols and gels belong to colloids. Then, what's the difference between them? Please follow us.
Table 1. The difference between sols and gels
| Items | Sols | Gels |
| Description | Sols are a colloidal solution suspension of very small solid particles in a continuous liquid medium, which is stable and shows the Tyndall effect. | Gels are special colloids consisting of two or more phases. |
| Alternative Description | Sols are the liquid state of a colloidal solution. | Gels can be described as a solid or semi-solid stage of a colloidal solution. |
| Disperse Phase | Solid | Liquid or gas |
| Dispersion Medium | The dispersion medium of the sols may be water (hydrosol) or alcohol (alcosol). | The dispersion medium of the gels is hydrated colloid particles. |
| Conversion | Sols can be converted to gels by cooling. | Gels can be converted to sol by heating. |
| Definite Structure | Sols have no definite structure. | Gels generally have a honeycomb-like structure. |
| Dehydration | Dehydration of the sols are relatively easy. | Dehydration of gels is not possible. |
| Viscosity | The viscosity of the sols are very low. | The viscosity of the gels is very high. |
| Examples | Blood, pigmented ink, paint, cell fluids, milks, muds, etc. | Fruit jelly, cooked gelatin jelly, fog, mist, ice cloud, hair spray, cheese, butter, etc. |
Note: Tyndall Effect is the scattering of visible light by colloidal particles.
Sols and gels have a wide range of applications in daily life, so it is very necessary to fully understand their properties and differences. For many years, Alfa Chemistry is passionate about the research of colloids, including sol and gels. No matter what problem you have, please feel free to contact us. We look forward to working with you.
Please kindly note that our products and services are for research use only.
