Mixture

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For other uses, see Mixture (disambiguation).

In chemistry, a mixture is 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. While there are no chemical changes in a mixture, physical properties of a mixture, such as its melting point, may differ from those of its components. Mixtures can usually be separated by mechanical means.

1 Types of mixtures
2 See also

[edit] Types of mixtures

There are three different types of mixtures: homogeneous mixtures (also called solutions), heterogeneous mixtures, and colloidal dispersions.

[edit] Homogeneous mixtures

Homogeneous mixtures are mixtures that have a definite composition and properties, for example, any amount of a given mixture has the same composition and properties. Examples are solutions and some alloys (but not all). Homogeneous mixtures can also be called "impure substances." A homogeneous mixture is a uniform mixture consisting of only one phase.

[edit] Solutions

Main article: Solution

One type of homogeneous mixture is a solution. A solution is a homogeneous mixture of two or more substances (the solutes) dissolved in another substance (the solvent). A common example would be a solid dissolving into a liquid, for example salt or sugar dissolving in water (or even gold into mercury). Liquids dissolve into one another, and sometimes liquids dissolve into gases, for example water vapor in the atmosphere. Common examples include soft drinks (like Coca-Cola and Sprite), where carbon dioxide is trapped in the soda through carbonation.

[edit] Heterogeneous mixtures

Heterogeneous mixtures are mixtures without definite composition, for example, granite. Salad is a typical example of this kind of mixture. Heterogeneous mixtures are said to have several phases (not to be confused with phases of matter). An example is the parts of a heterogeneous composition, which can be mechanically separated from the rest. Examples include: salad, trail mix, milk (before homogenization).

[edit] Colloidal dispersions

Main article: Colloid

In general, a colloid or colloidal dispersion is a substance with components of one or two phases, a type of mixture intermediate between a homogeneous mixture and a heterogeneous mixture with properties also intermediate between the two. A colloid will not settle if left to sit. Examples are jello, glue, and sperm.