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A suspension of flour in water, a heterogeneous mixture

In chemistry, a mixture is a material system made up by two or more different substances which are (mixed) together but are not combined chemically. Mixture refers to the physical combination of two or more substances the identities of which are retained. The molecules of two or more different substances are mixed in the form of alloys, solutions, suspensions, and colloids.

Mixtures are the product of a mechanical blending or mixing of chemical substances like elements and compounds, without chemical bonding or other chemical change, so that each ingredient substance retains its own chemical properties and makeup.^[1] Nonetheless, despite there are no chemical changes to its constituents, the physical properties of a mixture, such as its melting point, may differ from those of the components. Some mixtures can be separated into their components by mechanical means; azeotropes cannot, at least not directly.

Mixtures can be either homogeneous or heterogeneous. A homogeneous mixture is a type of mixture in which the composition is uniform. A heterogeneous mixture is a type of mixture in which the composition can easily be identified, as there are two or more phases present. Air is a homogeneous mixture of the gaseous substances nitrogen, oxygen, and smaller amounts of other substances. Salt, sugar, and many other substances dissolve in water to form homogeneous mixtures. A homogeneous mixture in which there is both a solute and solvent present is also a solution.

Types of mixtures

Dissolved or dispersed phase	Continuous medium	Solution: Homogeneous mixture: Dissolved phase < 1 nanometer	Colloid: Dispersed phase between 1 nanometer and 1 micrometer	Dispersion: Heterogeneous mixture: Dispersed phase > 1 micrometer
Gas	Gas	Gas mixture: air (oxygen and other gases in nitrogen)	None	None
Liquid	Gas	None	Aerosol: fog, mist, vapor, hair sprays	Aerosol
Solid	Gas	None	Solid aerosol: smoke, cloud, air particulates	Solid aerosol: dust
Gas	Liquid	Solution: oxygen in water	Foam: whipped cream, shaving cream	Foam
Liquid	Liquid	Solution: alcoholic beverages	Emulsion: miniemulsion, microemulsion	Emulsion: milk, mayonnaise, hand cream
Solid	Liquid	Solution: sugar in water	Sol: pigmented ink, blood	Suspension: mud (soil, clay or silt particles are suspended in water), chalk powder suspended in water
Gas	Solid	Solution: hydrogen in metals	Solid foam: aerogel, styrofoam, pumice	Foam: dry sponge
Liquid	Solid	Solution: amalgam (mercury in gold), hexane in paraffin wax	Gel: agar, gelatin, silicagel, opal	Wet sponge
Solid	Solid	Solution: alloys, plasticizers in plastics	Solid sol: cranberry glass	Gravel, granite

References

^ Atkins' Physical Chemistry, 7th Ed. by Julio De Paula, P.W. Atkins ISBN 0198792859

IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "mixture". doi:10.1351/goldbook.M03949

[1] Atkins' Physical Chemistry, 7th Ed. by Julio De Paula, P.W. Atkins ISBN 0198792859

[1]

@@ Line 3: / Line 3: @@
 [[Image:WaterAndFlourSuspensionLiquid.jpg|thumb|A [[suspension (chemistry)|suspension]] of flour in water, a heterogeneous mixture]]
-In [[chemistry]], a '''mixture''' is  a material system made up by two or more different [[chemical substance|substances]] which are ([[mix]]ed) together but are not combined chemically.  The molecules of two or more different substances are mixed in the form of [[alloy|alloys]], [[solutions]], [[suspensions]], and [[colloids]].
+In [[chemistry]], a '''mixture''' is  a material system made up by two or more different [[chemical substance|substances]] which are ([[mix]]ed) together but are not combined chemically. Mixture refers to the physical combination of two or more substances the identities of which are retained. The molecules of two or more different substances are mixed in the form of [[alloy|alloys]], [[solutions]], [[suspensions]], and [[colloids]].
 Mixtures are the product of a [[wikt:blend|mechanical blending]] or mixing of [[chemical substance]]s like [[chemical element|elements]] and [[chemical compound|compounds]], without chemical bonding or other chemical change, so that each ingredient substance retains its own chemical properties and makeup.<ref>Atkins' Physical Chemistry, 7th Ed. by Julio De Paula, P.W. Atkins ISBN 0198792859</ref> Nonetheless, despite there are no chemical changes to its constituents, the physical properties of a mixture, such as its [[melting point]], may differ from those of the components. Some mixtures can be [[separation process|separated]] into their components by mechanical means; [[azeotrope]]s cannot, at least not directly.
-Mixture refers to the physical combination of two or more substances the identities of which are retained. Mixtures can be either [[homogeneous (chemistry)|homogeneous]] or [[heterogeneous]]. A homogeneous mixture is a type of mixture in which the composition is uniform. A heterogeneous mixture is a type of mixture in which the composition can easily be identified, as there are two or more phases present. Air is a homogeneous mixture of the gaseous substances nitrogen, oxygen, and smaller amounts of other substances. Salt, sugar, and many other substances dissolve in water to form homogeneous mixtures. A homogeneous mixture in which there is both a [[solute]] and [[solvent]] present is also a solution.
+Mixtures can be either [[homogeneous (chemistry)|homogeneous]] or [[heterogeneous]]. A homogeneous mixture is a type of mixture in which the composition is uniform. A heterogeneous mixture is a type of mixture in which the composition can easily be identified, as there are two or more phases present. Air is a homogeneous mixture of the gaseous substances nitrogen, oxygen, and smaller amounts of other substances. Salt, sugar, and many other substances dissolve in water to form homogeneous mixtures. A homogeneous mixture in which there is both a [[solute]] and [[solvent]] present is also a solution.
 ==Types of mixtures==