Even though matter can be found all over the Universe, you will only find it in a few forms on Earth. We cover five states of matter on the site. Each of those states is sometimes called a phase. There are many other states of matter that exist in extreme environments. Scientists will probably discover more states as we continue to explore the Universe.

What makes a state of matter? It's about the physical state of the molecules and atoms. Think about solids. They are often hard and brittle. Liquids are fluidy, can move around a little, and fill up containers. Gases are always around you, but the molecules of a gas are much farther apart than the molecules in a liquid. If a gas has an odor, youll be able to smell it before you can see it. The BEC is all about atoms that are even closer and less energetic than atoms in a solid.

So you're asking, "What is a chemical change?" Let's start with a glass of pure water. If the formula of water were to change, that would be a chemical change. If you could add a second oxygen atom to a water molecule, you would have hydrogen peroxide (H2O2). The molecules would not be water anymore. The reality of creating hydrogen peroxide is more difficult.

Chemical changes occur when the bonds between atoms in a molecule are created or destroyed. Changes in the physical state are related to changes in the environment such as temperature, pressure, and other physical forces. Generally, the basic chemical structure does not change when there is a physical change. Of course, in extreme environments such as the Sun, no molecule is safe from destruction.

Continued here:
Chem4Kids: Matter - Rader's CHEM4KIDS.COM - Chemistry ...