What’s the difference between a homogeneous and heterogeneous mixture?
Submitted by: Emma G
Last date updated: 9/29/11

What are Compounds and Elements?

Compounds are made up of two or more elements that have undergone a chemical change. But compounds are composed of two or more kinds of atoms. Some compounds are water, salt and sugar. Compounds are made up of different elements but elements are made up of lots of the same atom. The number of known compounds (both natural and artificial) is in the millions. A sample of a pure element contains atoms that are chemically the same. Copper contains only copper atoms and oxygen contains only oxygen atoms.

What is a mixture?

Matter made of two or more substances mixed together but not chemically combined. An example of a mixture is, Sand because it is made up of sand, rocks and other minerals. When you mix sand rocks and other minerals together it is a mixture because you still have sand rocks and other minerals that you can separate. Then when you mix baking soda and vinegar together it fizzes and forms gas and carbon dioxide which makes it not a mixture because you can’t separate the vinegar and baking soda. It’s not a mixture but it is a chemical reaction because when they react it’s making new stuff, gas and carbon dioxide.


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This is a greek salad, which is a heterogeneous mixture because it is not evenly mixed and the ingredients are chunk and they are noticeable
What is a homogeneous mixture?

A homogeneous mixture is a substance in which components are evenly mixed. Also in homogeneous mixtures you can’t noticeably see the ingredients. Some examples of homogenous mixtures are smooth peanut butter, milk, perfume and paint. Perfume is a homogenous mixture because you can’t pick out the ingredients or obviously see them.



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Perfume is a homogeneous mixture because it IS evenly mixed and you cant noticeably see the ingredients












What is a heterogeneous mixture?

A heterogeneous mixture is a substance in which components are not evenly mixed. In heterogeneous mixtures you can noticeably see the ingredients. Examples of heterogeneous mixtures are a sandwich, honey bunches of oats, and salads and certain salad dressings. Salad is a heterogeneous mixture because you can see it’s not evenly mixed and you can pick out all the ingredients.

How do you separate a mixture?

Mixtures don’t have definite composition. Mixtures can be separated by evaporation, distillation, crystillation, and filtration.

Evaporation

Evaporation is the liquid boiling that turns into gas and floats away laving whatever solid is there. An example is if you take a pot of salt water from the ocean and you boil it the water will evaporate and turn into gas and float away leaving behind a lot of salt.

Distillation

Distillation is two different liquids that are boiled that turn into gas at a different temperature. An example of distillation if you take two different liquids and one boils at 100 degrees and one boils at 200 degrees, if you put them both in a pot and turn it on to 100 degrees one will boil and turn into gas and float away while the other liquid sits in the pot unless you turn the temperature up to 200 degrees.

Filtration

Filtration is running a mixture through a machine that has different size holes in it depending on what you want to let through. An example of filtration is when you make pasta you pour the water and pasta you just boiled the pasta in and put it into a strainer and all the water goes through the holes leaving behind the pasta.

Crystillation

Crystillation is the stuff that dissolved going from a liquid to a solid. Some examples of crystillation are when you make rock candy the sugar dissolves in the water when you boil it but it wants to turn back into a solid, so when you put a crystal back in the pot it all grabs onto it and when it cools on it, it forms back.


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This is a comparison of homogeneous and heterogeneous mixtures






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Glossary

Distillation- Distillation is two different liquids that are boiled that turn into gas at a different temperature.

Filtration- Filtration is running a mixture through a machine that has different size holes in it depending on what you want to let through

Compounds- Compounds are made up of two or more elements that have undergone a chemical change. Compounds are composed of two or more kinds of atoms

Carbon Dioxide- what vinegar, baking soda and water create when they are combined

Atoms- the smallest part of matter that is used as a building block

Citations

Database: "chemistry." Compton's by Britannica. Encyclopædia Britannica Online School Edition.

Encyclopædia Britannica, Inc., 2011. Web. 26 Sept. 2011.

<http://school.eb.com/all/comptons/article-229350>.

Database: Citation (MLA)

Heterogeneous and Homogeneous Mixtures. Prod. Brian Jerome. Brian Jerome, 1998. Discovery Education. Web. 26 September 2011. <http://www.discoveryeducation.com/>.

Book: Friedhopper, Bob Science Lab in a Supermarket, Ne York Franklin Watts 1998 Print