kolloïden

Kolloïden, also known as colloidal dispersions, are mixtures where one substance of extremely fine particles is dispersed evenly throughout another substance. These particles are larger than individual molecules but too small to be seen with the naked eye or even a standard microscope. The dispersed particles, often called the disperse phase, remain suspended in the continuous phase, which is the medium in which they are scattered.

Unlike true solutions where solutes are dissolved at a molecular level, the particles in a colloid do not settle out over time. This stability is due to the Brownian motion, the random movement of suspended particles caused by collisions with the molecules of the surrounding medium. Kolloïden exhibit the Tyndall effect, a phenomenon where a beam of light passing through the colloid becomes visible as the light is scattered by the dispersed particles. This effect is not observed in true solutions.

Examples of kolloïden are abundant in everyday life. Milk, for instance, is a colloid of fat globules dispersed in water. Smoke is a colloid of solid particles in air, while fog is a colloid of liquid water droplets in air. Paint is another common example, with pigment particles dispersed in a liquid binder. The properties of kolloïden depend on the size of the dispersed particles, their concentration, and the nature of both the dispersed and continuous phases.