What are 5 examples of heterogeneous?

ThoughtCo / Bailey Mariner

Updated on February 04, 2020

A heterogeneous mixture is a mixture with a non-uniform composition. The composition varies from one region to another with at least two phases that remain separate from each other, with clearly identifiable properties. If you examine a sample of a heterogeneous mixture, you can see the separate components.

In physical chemistry and materials science, the definition of a heterogeneous mixture is somewhat different. Here, a homogeneous mixture is one in which all components are in a single phase, while a heterogeneous mixture contains components in different phases.

Examples of Heterogeneous Mixtures

• Concrete is a heterogeneous mixture of an aggregate: cement, and water.
• Sugar and sand form a heterogeneous mixture. If you look closely, you can identify tiny sugar crystals and particles of sand.
• Ice cubes in cola form a heterogeneous mixture. The ice and soda are in two distinct phases of matter (solid and liquid). 
• Salt and pepper form a heterogeneous mixture.
• Chocolate chip cookies are a heterogeneous mixture. If you take a bite from a cookie, you may not get the same number of chips as you get in another bite.
• Soda is considered a heterogeneous mixture. It contains water, sugar, and carbon dioxide, which forms bubbles. While the sugar, water, and flavorings may form a chemical solution, the carbon dioxide bubbles are not uniformly distributed throughout the liquid.

Homogeneous Vs. Heterogeneous Mixtures

In a homogeneous mixture, the components are present in the same proportion no matter where you take a sample. In contrast, samples taken from different parts of a heterogeneous mixture may contain different proportions of components.

By way of example, if you take a handful of candy from a bag of green M&Ms, every candy you pick will be green. If you take another handful, once again all the candies will be green. That bag contains a homogeneous mixture. If you take a handful of candy from a regular bag of M&Ms, the proportion of colors you take might be different from what you get if you take a second handful. This is a heterogeneous mixture.

Most of the time, whether a mixture is heterogeneous or homogeneous depends on the scale of the sample. Using the candy example, while you may get a different sample of candy colors comparing handfuls from a single bag, the mixture may be homogeneous if you compare all the colors of candies from one bag to all the candies from another bag. If you compare the ratio of colors from 50 bags of candy to another 50 bags of candy, chances are good there will be no statistical difference between the ratio of colors.

In chemistry, it is the same. On the macroscopic scale, a mixture may appear homogeneous, yet become heterogeneous as you compare the composition of smaller and smaller samples.

Homogenization

A heterogeneous mixture can be made into a homogeneous mixture via a process called homogenization. An example of homogenization is homogenized milk, which is processed so that the milk components are stable and don't separate.

In contrast, natural milk, while it might appear homogeneous when shaken, isn't stable and readily separates into different layers.

Watch Now: What's the Difference Between Homogeneous and Heterogeneous?

Updated on October 02, 2020

When you combine two or more materials, you form a mixture. In chemistry, a mixture is a combination that does not produce a chemical reaction. There are two categories of mixtures: homogeneous mixtures and heterogeneous mixtures. Here's a closer look at these types of mixtures and examples of mixtures.

Key Takeaways: Mixture

• A mixture is formed by combining two or more materials.
• A homogeneous mixture appears uniform, regardless of where you sample it. A heterogeneous mixture contains particles of different shapes or sizes and the composition of one sample may differ from that of another sample.
• Whether a mixture is heterogeneous or homogeneous depends on how closely you examine it. Sand may appear homogeneous from a distance, yet when you magnify it, it is heterogeneous.
• Examples of homogeneous mixtures include air, saline solution, most alloys, and bitumen.
• Examples of heterogeneous mixtures include sand, oil and water, and chicken noodle soup.

Homogeneous Mixtures

Homogeneous mixtures appear uniform to the eye. They consist of a single phase, be it liquid, gas, or solid, no matter where you sample them or how closely you examine them. The chemical composition is the same for any sample of the mixture.

Heterogeneous Mixtures

Heterogeneous mixtures are not uniform. If you take two samples from different parts of the mixture, they will not have an identical composition. You can use a mechanical method to separate components of a heterogeneous mixture (e.g., sorting candies in a bowl or filtering rocks to separate them from sand).

Sometimes these mixtures are obvious, where you can see different types of materials in a sample. For example, if you have a salad, you can see different sizes and shapes and types of vegetables. In other cases, you need to look more closely to recognize this mixture. Any mixture that contains more than one phase of matter is a heterogeneous mixture.

This can be tricky because a change of conditions can alter a mixture. For example, an unopened soda in a bottle has a uniform composition and is a homogeneous mixture. Once you open the bottle, bubbles appear in the liquid. The bubbles from carbonation are gasses, while the majority of the soda is liquid. An opened can of soda is an example of a heterogeneous mixture.

Examples of Mixtures

1. Air is a homogeneous mixture. However, the Earth's atmosphere as a whole is a heterogeneous mixture. See the clouds? That's evidence the composition is not uniform.
2. Alloys are made when two or more metals are mixed together. They usually are homogeneous mixtures. Examples include brass, bronze, steel, and sterling silver. Sometimes multiple phases exist in alloys. In these cases, they are heterogeneous mixtures. The two types of mixtures are distinguished by the size of the crystals that are present.
3. Mixing together two solids, without melting them together, typically results in a heterogeneous mixture. Examples include sand and sugar, salt and gravel, a basket of produce, and a toy box filled with toys.
4. Mixtures in two or more phases are heterogeneous mixtures. Examples include ice cubes in a drink, sand and water, and salt and oil.
5. The liquid that is immiscible form heterogeneous mixtures. A good example is a mixture of oil and water.
6. Chemical solutions are usually homogeneous mixtures. The exception would be solutions that contain another phase of matter. For example, you can make a homogeneous solution of sugar and water, but if there are crystals in the solution, it becomes a heterogeneous mixture.
7. Many common chemicals are homogeneous mixtures. Examples include vodka, vinegar, and dishwashing liquid.
8. Many familiar items are heterogeneous mixtures. Examples include orange juice with pulp and chicken noodle soup.
9. Some mixtures that appear homogeneous at first glance are heterogeneous upon closer inspection. Examples include blood, soil, and sand.
10. A homogeneous mixture can be a component of a heterogeneous mixture. For example, bitumen (a homogeneous mixture) is a component of asphalt (a heterogeneous mixture).

Not a Mixture

Technically, if a chemical reaction is occurring when you mix two materials, it's not a mixture... at least not until it has finished reacting.

• If you mix baking soda and vinegar, a chemical reaction occurs. Once the reaction has finished, the remaining material is a mixture.
• If you mix together ingredients to bake a cake, a chemical reaction occurs between the ingredients. While we use the term "mixture" in cooking, it doesn't always mean the same thing as the chemistry definition.

Watch Now: What's the Difference Between Homogeneous and Heterogeneous?