Colloid

Colloid or colloidal dispersion is a heterogeneous mixture that visually appears to be a homogeneous solution. A heterogeneous mixture is a mixture of two phases whereas a solution is one phase. In a colloid, 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 or droplets is typically between one nanometer and one micrometer. Heterogeneous mixtures with a dispersed phase in this size range may be called colloidal aerosols, colloidal emulsions, colloidal foams, colloidal suspensions or colloidal dispersions. The dispersed phase particles or droplets are largely affected by the surface chemistry present in the colloid.