Matter Study Guide 8th Grade Science www.middleschoolscience.com 2008

Matter Anything that has a mass and a volume

States of Matter Solid Liquid Gas Plasma Close up view of atoms and their behavior Animated images are from http://www.chem.purdue.edu/gchelp/

Physical vs. Chemical Change Changing from one state to another is a Physical Change. If a new substance is formed it is a Chemical Change. Images are from http://www.chem4kids.com

Atoms Elements The building blocks of Matter Consists of Protons (+), Electrons (-), and Neutrons (N). Elements Consists of only one kind of atom, Cannot be broken down into a simpler type of matter by either physical or chemical means Can exist as either atoms or molecules. Images are from http://www.chem4kids.com

Molecules A molecule consists of two or more atoms of the same element, or different elements, that are chemically bound together. In the animation above, two nitrogen atoms (N + N = N2) make one Nitrogen molecule .

Compounds Atoms of two or more different elements bound together. Can be separated into elements chemically, but not physically. In the animation above, water (H20) is a compound made of Hydrogen and Oxygen. Animated images and notes from http://www.chem.purdue.edu/gchelp/atoms/elements.html

Solutions Homogeneous Solutions are groups of molecules that are mixed up in a completely even distribution. Homogeneous Uniform Distribution. Example: Sugar and Water Images are from http://www.chem4kids.com

Solute Solvent The substance to be dissolved. The one doing the dissolving. Images are from http://www.chem4kids.com

Making a Solution

Colloids Particle sizes are in between the size of particles found in solutions and suspensions . Can be mixed and remain evenly distributed without settling out.

Mixtures Heterogeneous They are substances held together by physical forces, not chemical. Can be separated physically. Solutions are also mixtures. Heterogeneous The substances are not uniformly mixed. Example: Sand in a glass of water. Images are from http://www.chem4kids.com

Mixtures Suspensions Are heterogeneous mixtures consisting of parts that are visible to the naked eye. Substances will settle over time. Example: the ingredients in salad dressing

Matter Mixtures Homogeneous Heterogeneous Pure Substances Solvent Solution Solvent Colloids Heterogeneous Suspensions Pure Substances Element Molecule Compounds