Types of Mixtures

Pure substances are either elements or compounds. A sample of a pure substance contains only one element or one compound. Finding a pure substance is not so easy to do. Chemistry stockrooms around the world are filled with bottles and vials of seemingly pure substances for experiments. Upon closer examination of the reagent labels, even some chemicals intended for exacting lab procedures have a very small percentage of contamination, which is virtually impossible to remove. That makes them a mixture. A mixture contains one or more elements or compounds.

Some mixtures are quite easy to pick out because you can actually view and observe the different substances. A prime example of a mixture where you can see the different substances is soil. When you view soil, all of the different components are easily separated. Soil is really a mixture of water, air, organic material, sand, silt, and clay. Other mixtures contain microscopic particles that are only viewed with the aid of technology. Salt water is a great example of this type of mixture. Salt water is made up of many elements, but those individual elements are impossible to observe. In this topic, you will learn about the about the different types of mixtures.

Essential Questions

• What is the difference between a colloid, suspension, and solution?
• What is the difference between a heterogeneous and homogeneous mixture?