Colloid facts for kids

A colloid may be a mixture of one substance that may spread out evenly inside another substance. They may be in two different phases or states of matter.

One substance can be the dispersion medium, such as water or gas. The other is kind of dispersed medium, sometimes called the 'internal phase'. This is never tiny solid particles. Otherwise, if the dispersion medium is a gas, then the internal phase may be either tiny particles or tiny droplets of a liquid.

Definition: A colloid is a substance microscopically dispersed evenly throughout another substance. The dispersed-phase particles have a diameter between about 5 and 200 nanometers. Colloids can be classified as follows:

Medium/phase		Dispersed phase
		Gas	Liquid	Solid
Dispersion medium	Gas	No such colloids are known Helium and Xenon are known to be immiscible under certain conditions.	Liquid aerosol Examples: fog, clouds, mist, hair sprays	Solid aerosol Examples: smoke, ice cloud, atmospheric particulate matter
	Liquid	Foam Example: whipped cream, shaving cream	Emulsion Examples: milk, mayonnaise, hand cream; latex	Sol Examples: pigmented ink, blood
	Solid	Solid foam Examples: aerogel, styrofoam, pumice	Gel Examples: agar, gelatin, jelly	Solid sol Example: cranberry glass

Images for kids

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  Milk

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  Fog

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  Shaving cream

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  Styrofoam

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  Pumice

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  Whipped cream