What Are Mixtures in Science?

A mixture is the result of combining two or more substances that do not react chemically. In order for a solution or combination to be labelled as a mixture, it must be possible to separate the individual components through physical means, without resorting to chemical reactions.

The two types of mixtures are heterogeneous mixtures and homogeneous mixtures. Homogeneous mixtures are uniform mixtures with components that are not easily distinguishable through simple observation. Components in a homogeneous mixture are not easily separated by mechanical means and are all in the same state of matter, meaning that a homogeneous mixture is composed of exclusively gas, liquid, or solid components. Examples of homogeneous mixtures include metal alloys, sugar water and vinegar.

Heterogeneous mixtures contain components of a variety of shapes and sizes and are not uniform. The components of a heterogeneous mixture are not required to be identical or similar in any way to each other and can present in different states of matter, such as cereal in milk. It is typically easier to distinguish and separate the individual components of a heterogeneous mixture than those of a homogeneous mixture. Other examples of homogeneous mixtures include mixed nuts, ice in soda and sand or gravel.