American Chemical Society
Middle School Chemistry: Changing State Freezing
Discover how freezing works, when the change of state moves from liquid to solid.
Kent State University
Kent State: Classification of Matter
Nice tree structure which shows the different separation technique needed for the two sides. Also gives examples of physical changes/separation techniques.
American Chemical Society
Middle School Chemistry: Changing State Melting
Explore the phase change that occurs when ice is melting.