A<unk>  or<unk> al dispersion is a type of heterogeneous mixture. A<unk>  consists of two separate phases: a dispersed phase and a continuous phase. In a<unk> , the dispersed phase is made of tiny particles or droplets that are distributed evenly throughout the continuous phase. The size of the dispersed phase particles are between 1 nm and 1000 nm in at least one dimension. Homogeneous mixtures with a dispersed phase in this size range may be called<unk> al aerosols,<unk> al emulsions,<unk> al foams,<unk> al dispersions or hydrosols. The dispersed phase particles or droplets are largely affected by the surface chemistry present in the<unk> .
Because the size of the dispersed phase may be hard to measure, and because<unk> s look like solutions,<unk> s are sometimes characterized by their properties. For example, if a<unk>  has a solid phase dispersed in a liquid, the solid particles will not pass through a membrane, whereas the dissolved ions or molecules of a solution will pass through a membrane. In other words, dissolved components will diffuse through a membrane through which dispersed<unk> al particles will not.
Some<unk> s are translucent because of the Tyndall effect, which is the scattering of light by particles in the<unk> . Other<unk> s may be opaque or have a slight color.
Many familiar substances, including butter, milk, cream, aerosols (fog, smog, smoke), asphalt, inks, paints, glues, and sea foam are<unk> s. This field of study was introduced in 1861 by Scottish scientist Thomas Graham.
Colloid
Fluid
Fluence
Polyethylene
Filter 
Biodiesel
Stye
Ionic liquid