classification+of+matter

Matter is the focus of chemistry - how it interacts with other forms of matter, with energy, and its physical or chemical properties.

The classification of a substance is based on //qualitative// observation, meaning its visual description. However, some properties are //quantitative// (based on measurement), such as density or melting point.

Matter can be classified into a number of categories:

Each category has a specific description.


 * Mixture:** more than one type of material physically combined.
 * If the parts of the mixture cannot be seen by the eye, and the mixture is uniform, it is called a homogeneous mixture.
 * If the parts of the mixture can be seen, and are different from one another (not uniform), it is called a heterogeneous mixture.


 * Question:** Classify the following mixtures as either homogeneous or heterogeneous.




 * Pure substance:** a material composed of identical parts.
 * A __compound__ is composed of more than one atom chemically bonded to one another in fixed ratios. Water, H2O, is an example.
 * An __element__ is a material that is composed of identical atoms, like a gold nugget. Democritus had this concept in mind with his term //atomos.//






 * Question:** identify the type of pure substance (element or compound?) in each of the following images.



Here is a web site that contains online practice and worksheets.

You can download this practice worksheet:

And this one: or this one: Try this AP Chemistry worksheet dealing with classifying matter.